Santa Bárbara mining complex

Description

The mercury-producing district of Huancavelica is located at the heart of the Andes range, at 3,700 meters above sea level, 245 kilometers southeast of Lima. Mercury or quicksilver production in Huancavelica was the largest of the Western hemisphere and it holds the fourth position of the world ranking, only bettered by Almadén (Spain), Idrija (Slovenia) and Mount Amiata (Italy). Most mercury mining activities took place between 1571 and 1790, and they were mainly conducted in Santa Bárbara mine, the most important mine site of Huancavelica. The critical role of mercury in the colonial economy caused Viceroy Francisco de Toledo to found the city of Huancavelica calling it "Villa Rica de Oropesa".

The significance of Huancavelica mines is due to the essential role that mercury had in the colonial economy, based on the exploitation of precious metals. Short after the conquest of the New World, gold and silver exploitation began using traditional indigenous methods, with which superficial ore veins –rich in native gold and silver- were exploited. However, after a few years these veins started being depleted, thus it was necessary to start mining at greater depths. At the same time, technological innovations created methods that allowed extracting the largest amount of precious metals from low-grade ore.

At the beginning, gold and silver were refined using the smelting method, which does not need mercury but plenty of firewood. In 1555, a Sevillian man, Bartolomé de Medina, developed the mercury amalgamation or cold amalgamation method, which is much more efficient and economic than the smelting method. Through amalgamation, rocks with precious metal content were crushed to produce fine sand, which was then mixed with water, salt, lime and magistral (a mix of copper and calcined iron). Mercury or quicksilver was added to this mix, which was then treaded for several days to combine the mix with mercury. The mix was then washed and heated, evaporating mercury and leaving silver and gold apart from other ore. Finally, the resulting material was casted into ingots.

The new method disseminated quickly in Spain and its colonies, which resulted in the boom of silver mining and export to Europe, since it allowed using lower-grade ore, with lower silver content, and a lower consumption of firewood.

The higher demand of mercury caused by the discovery of the new technique to obtain silver, led to the finding of Santa Bárbara mine deposits in Huancavelica, in 1564. Initially, it covered the demand of the San Luis de Potosí silver mines in Mexico, whenever the supply from Almadén (Spain) and Idria (Slovenia) mines was not enough. Afterwards, quicksilver from Huancavelica was used mainly in the Cerro Rico de Potosí mines (1545), in current Bolivia, which produced two thirds of the total silver exported to Spain in almost 300 years.

Father Jose Acosta (1540-1600) pointed out "En tiempo que gobernaba el Pirú D. Francisco de Toledo, un hombre que havía estado en México y visto cómo se sacaba plata con los azogues, llamado Pedro Fernández de Velasco, se ofreció de sacar la plata de Potosí por azogue; y hecha la prueba y saliendo muy bien, el año de setenta y uno se comenzó en Potosí a beneficiar la plata con los azogues que se llevaron de Huancavelica, y fue el total remedio de aquellas minas, porque con el azogue se sacó plata infinita de los metales que estaban desechados, que llamaban desmontes". ("In the time when D. Francisco de Toledo governed Piru, a man who had been in Mexico and had seen how silver was extracted with quicksilver, called Pedro Fernandez de Velasco, volunteer to extract silver from Potosí with quicksilver; and after the test came out very well, in 1571 Potosí started to extract silver with mercury brought from Huancavelica, and it was a good solution for those mines, because thanks to mercury it was possible to extract infinite silver from already discarded ore, which was called waste". Free translation. ACOSTA 1979: book. IV, chapter XI, 161-162).

Having proved the usefulness of such ore and having ensured silver production in Potosí thanks to the amalgamation method, the Spanish crown became aware of the strategic significance of Santa Bárbara mercury mine, thus expropriating the 43 mines discovered at that time from their discoverer Amador de Cabrera and his partners Jose Tamayo,Pedro de Aliaga, the Marquis of Monterrico, Alcocer and Pedro de Alarco, among others, in 1572-73. In order to ensure the permanent exploitation of the mines and considering that the State lacked the capacity to do the job, the Viceroy Francisco Toledo established a private concession system with the members of the Association of Miners, with which a long-term lease agreement –called "Asiento"- was entered into. According to this system, the miners were in charge of exploiting and smelting ore at their own expense, having an obligation to sell the total mercury production to the Crown at a price previously fixed by the viceregal administration, once the Quinto Real had been withheld, and then it was sold at a higher price to the Potosí miners. In exchange, the crown agreed to provide indigenous labor to the tenants and to give specific amounts of money in advance for mining and smelting activities.

Mining exploitation required special infrastructure and a large amount of labor, thus Viceroy Francisco Toledo instituted the mining mita, a forced collective labor system based on a rotational public service organized during the Incan empire, through which indigenous people between 18 and 50 years from tax provinces located within a 40-league radius (approximately 223 km) from mining centers, had to work in the mines for a year in exchange of a small economic retribution, sort of a wage or weekly salary, and some additional "benefits", such as small supplies of beef and corn. Such provision forced a large amount of people to move from their hometowns to work under hazardous and unhealthy conditions due to the high toxicity of mercury, mines collapsing and extreme weather conditions, among other factors. Santa Bárbara mita, with more than 300 indigenous people coming from places as far as Andahuaylas and Tarma, constituted the largest forced labor location in the New World after Potosí mines. Workers settled in the mining camps that were mainly in Santa Bárbara and Chaccllatacana, as well as in the peripheral neighborhoods of Huancavelica city, such as Santa Ana, San Cristobal, Ascensión and San Sebastián. On March 19, 1812 the Cortes de Cadiz enacted the Cadiz Constitution, which –among other aspects- abolished taxes and the mita in all its variations, and granted citizenship to indigenous people.

Since the end of the XVI century, mercury distillation technology was based on "Hornos Jabecas" (furnaces called jabecas), which were used in Almadén mine, Spain. Quicksilver from Almadén was exported to Mexico after a long and expensive journey across the Atlantic Ocean, thus it was necessary to find quicksilver sources in America, to lower production and transport costs.

The growing mercury demand promoted a progressively more sophisticated technology for mercury distillation from cinnabar; on the other hand, it promoted a systematic search for local sources of liquid metal. Due to technological improvements created in Huancavelica, Pedro de Contreras introduced a series of changes to the "hornos de jabecas" at the end of the XVI century, altering the furnaces’size and other elements, and using ichu (Peruvian feathergrass) –a grass abundant in that area that produces higher thermal energy than firewood- as fuel, which significantly improved smelting furnaces’ production. These innovations were used for 40 years until the "Hornos de Aludeles" (aludeles furnaces) first appeared in 1633, which were invented by Lope Saavedra Barba from Huancavelica. This technology was later taken to Almadén, where it was called "Hornos de Bustamante", because it was Juan Alonso de Bustamante who introduced it in Spain in 1646.

The "hornos de Aludeles" replaced the "Jabecas", which had been used to distil mercury since the end of the XVI century. Used for the first time in mercury mines in Huancavelica, and then took to Almadén and Idria, aludeles furnaces decomposed cinnabar with oxygen taken from the air at a large scale using heat, which allowed increasing mercury production to industrial levels. New furnaces quickly displaced the jabecas, since they used less fuel and allowed working with larger amounts of ore at the same time (more than 100 quintals per burning), besides obtaining larger yields and being cleaner for working purposes, since the toxic effects of mercury vapors on workers’ health were well known.

The productive process of quicksilver or mercury required a series of steps: once the ore (cinnabar) was extracted from the endless mine galleries, it was crushed with maces or mortars to obtain small pieces that were then taken to smelting furnaces, generally located near to the mine openings or in the surroundings of Huancavelica city, where ore was heated at high temperatures using ichu and duff as fuel until mercury was evaporated, resulting then in liquid metal by vapor condensation after the cool-down process. The liquid metal was gathered in small bottles or in leather containers (badanas) and transported on lamas to the Caja Real (agency in charge of public accounting) in Huancavelica city, where it was weighed and stored before shipping it to silver mines.

The relevance of Santa Bárbara mine in Huancavelica is that it was the only significant mercury mine in the entire American continent until the California mines appeared in the mid-XIX century, and it was also the first mine where "hornos aludeles" were used. It is due to mercury mining in Santa Bárbara that several towns were born, both in its surroundings as well as along the route to its final destination. Since mercury was essential for silver and gold refining processes, which dominated the economy of Hispano-American colonies between XVI and XVIII centuries, Huancavelica became the main mercury supplier of Andean mines and eventually of all mines in the American continent.

Mercury production experienced periods of abundance and decline, ranging among two thousand and twelve thousand quintals per year (1 quintal = 46 kg), reaching its peak production between the end of the XVI century and the middle of the XVII century, with a brief upturn in mid-XVIII century (1758-1764 approximately), significantly falling by the end of the XVIII and XIX centuries due to the depletion of the mine’s producing veins, as well as to mine collapses (1786) which caused hundreds of deaths and rendered many galleries useless; besides the inefficient State administration, the significant reduction of mitaya labor, disorganized and unsafe work conditions and the fall of silver production in Potosí, with which Santa Bárbara mine’s decline started.

During the XVIII century several attempts to improve the mining system in Santa Bárbara were made by the colonial government, in order to achieve a more efficient production. Up to 1735 mine management was in the hands of an Oidor of the Real Audiencia de Lima, who simultaneously ruled the Huancavelica corregimiento. Since 1735 a Superintendent was appointed as Mine Governor, who was exclusively in charge of managing the mine. The first Superintendent was the Spanish Jerónimo de Sola y Fuente, who brought his relevant experience in the Almadén mines. Sola y Fuente introduced new ways of working and perfected the use of powder for mine exploitation way before it was used in Almadén, thus improving production. He also managed to find the mother lode, which had been lost since 1630.

After abolishing the Association of miners, the crown assumed the direct management and financial responsibility of the mine with adverse results, which caused that in 1792 the Viceroy Gil de Taboada authorized the free exploitation of any mine located within a 10 league radius (approximately 55 km) from the mine, with a single condition: that mercury produced had to be sold to the State warehouses at the official price of 85 pesos per quintal. This decision meant giving the mine away to small informal miners, known as pallaqueros, humaches or humachis, most of them indigenous. These were sort of wanderer miners, without capital or mining rights, who worked on their own at a level that -in general- was only enough to survive. In 1806, due to the lack of organization and to extremely unsafe working conditions, Santa Bárbara mine collapsed. Since that moment almost the entire mine has been disabled. In 1813 the Crown’s control system was declared over, and the monopoly on the sale of mercury was terminated.

After the independence from the Peruvian viceroyalty in 1821, the mine was in poor conditions and almost abandoned, and the new State failed to develop projects and to find a way to recover Huancavelica’s production. 

The State retained the mine’s ownership or direct control, but it did not exploit it directly, trying to rent it to private entrepreneurs, under the scheme used in colonial times up to the first half of the XIX century, though with a low production. Since 1850, mercury from California mines, in the United States, caused the definitive crisis of Santa Bárbara mine, incapable of competing with the imported product’s lower price. Only humaches remained active, until 1915 when the entrepreneur Eulogio Fernandini de la Quintana became the mine’s owner.

The Mining Act and the Mining Code, enacted in 1899 and 1900, correspondingly, provided the mining sector with greater dynamism during the first years of the XX century, since private investment in the sector was promoted. Exploitation of Santa Bárbara mine by Eulogio Fernandini de la Quintana is a remarkable example of this. He commissioned specialized soil studies and explorations of Santa Bárbara’s ore, he ordered foreign machinery, and rehabilitated the old gallery "Belén", which was 1,200 m long. To use the imported machinery, he installed a small hydroelectric power plant in the Sacsamarca River, which supplied electric power even to Huancavelica city, besides other complementary facilities, such as a cable car for ore transportation to the treatment plant, warehouse, central workshop, commercial registry and the mining camp, which structures are still there. Santa Bárbara mine rehabilitation revitalized Huancavelica city.

Towards 1940, Fernandini promoted a new development for Santa Bárbara mining production, by starting open pit mining operations in the old location, where the mine was discovered -the main mining center during the Viceroyalty- and rehabilitating the old Chaccllatacana deposit. In 1956, after he passed away, "Sociedad Minera El Brocal S.A." was formed and it continued working in Chaccllatacana mine, introducing technology innovations that allowed mining operations between 1968 and 1970, which continued to a lesser extent until 1975, when the dramatic drop of the international price of mercury brought mining activities to an end.

"El Brocal" treatment plant, initiated by Eulogio Fernandini de la Quintana in the beginning of the XX century, is an important testimony of the last revival of mercury mining in Huancavelica in the XX century, historically associated to the colonial exploitation of Santa Bárbara mine, after over 100 years of decline and abandonment. It is particularly significant as a substantial testimony of the evolution of technology applied to quicksilver treatment, which developed autonomously during colonial times thanks to Lope Saavedra Barba’s works, whose innovation the "Aludeles furnace" had an essential impact on the transformation of the mercury distillation technique globally. Inside the modern industrial plant we can still appreciate the combination of basic principles of traditional mining with cutting-edge technology imported and adapted to the rough conditions of the area.

The Huancavelica mercury route in the Viceroyalty of Perú

Between XVI and XVIII centuries, Huancavelica mercury was destined to the most important mines of the Viceroyalty of Perú and the Viceroyalty of Mexico or Nueva España. Within the Viceroyalty of Perú, the main consumer was Cerro Rico de Potosí mine in the Alto Perú (Upper Perú) area, currently Bolivia. Other important mines were Porco and Oruro (Bolivia), Yauricocha or Cerro de Pasco (Pasco, Perú), Castrovirreyna and Julcani (Huancavelica, Perú), Huarochiri (Lima, Perú), Lucanas (Ayacucho, Perú), Caylloma and Hauntajaya (Arequipa, Perú), San Antonio de Esquilache and Laycacota (Puno, Perú), Copiapó, Uspallata, Combarbala, Rancagua (Chile), among others. Moreover, it occasionally supplied the mines of the Viceroyalty of Nueva España (currently Mexico), mainly San Luis de Potosí mine, when Almadén was not able to meet the required deliveries.

Mercury transportation to Potosí, a mine located 336 leagues (1680 km) south from Huancavelica, main mining center in the American continent at the port of Tambo de Mora, to continue its trip to the port of Arica. Sea transport usually took place twice a year, and sometimes it was in charge of private carriers, when official ships were not available.

In Arica, mercury was unloaded, weighed again and stored in the Caja Real specifically equipped for that purpose. Afterwards, it was packed in mules that came from Chile and Tucuman (Argentina), which were more resistant than lamas to travel through the dessert, with scarce water and without shade, and had a larger carrying capacity (ten to twelve arrobas, as compared to three arrobas carried by a lama), to continue the journey to Potosí (ninety to one hundred leagues – 450 to 500 km, approximately) and Oruro, in order to supply Cerro Rico and San Cristobal silver mines, as well as other mines in the Andean highlands, such as Berenguela, Porco, etc.

Historian Antonio Vásquez de Espinoza (15??-1630) stated in his Compendio y Descripción de las Indias Occidentales that "… después, una vez fundido y sacado el azogue, lo ponen en badanas para guardarlo en los almacenes de Su Majestad y de allí lo llevan de ordinario en carneros al Puerto de Chincha (que está al Norte de Pisco 5 leguas) donde hay un almacén y factor proveído por el Real Consejo, que lo guarda en él y de allí lo embarca en navíos, hasta el Puerto de San Marcos de Arica, de donde se lleva en recuas, de carneros y mulas a Potosí". ("… then, after quicksilver had been smelted and extracted, they put it in containers to store it in Your Majesty warehouses, and from there they usually take it in lamas to the port of Chincha (5 leagues north from Pisco) where there is a warehouse and a representative provided by the Royal Council, which stores it in it, and then it is shipped to the port of San Marcos de Arica, from where it is taken in mules or lamas to Potosí". Free translation).

This transport system was widely used up to the second half of the XVIII century, and then it progressively declined due to the fall of mercury production in Santa Bárbara, caused by poor management, failure to find new veins and galleries that collapsed and could no longer be used, in addition to the importance gained by the ports of Buenos Aires (Argentina) and Montevideo (Uruguay) with the creation of the Viceroyalty of Rio de la Plata (currently Argentina), which made easier to transport mercury from Almadén (Spain) to Potosí through the Atlantic Ocean.

There was also a route used by smugglers, which was entirely by land or continental. It started in Huancavelica and joined, as stops: Huamanga, Cusco and Chucuito cities (the latter on the Titicaca lake shore), before entering La Paz city, and then crossing La Plata to arrive in Oruro and Potosí. This route should have taken advantage of part of the Main Andean Road or Qhapaq Ñan, and though it took much longer than the sea route, it allowed avoiding pirates surrounding the port of Arica.

According to the historian Alvaro Jara, it is a route that was used in the 1570s, when the route to go to Alto Perú (Andean highlands) mines was not yet well defined.

It may be said that the ports of Chincha, Pisco and Arica were born with quicksilver transportation, i.e. with the route of mercury. In those ports settled traders and working people, who helped transporting mercury with their jobs, doing business by renting animals and other supplies required for port activities. Mule breeding in Chile was born to supply these animals for quicksilver transportation from Arica to Potosí (mule packs made the journey back, carrying already refined silver). Furthermore, Huancavelica farmers found a business alternative for their lama packs, either to transport ore from the mine openings to the furnaces, or to transport it to San Jerónimo or to Julcani and Castrovirreyna mines. Chincha and Pisco valleys, as well as Moquegua and Tacna valleys, in the surroundings of the port of Arica, initiated wine and grape spirit production, meeting a great demand in the areas of Huancavelica and Potosí mines. The mercury mining industry in Santa Bárbara gave place to an economic corridor in the Huancavelica – Chincha – Pisco – Arica – Potosí route, around the route followed to transport mercury.

Relevance of the Santa Bárbara mercury mine

It is well known that gold and silver mining formed one of the strongest foundations of the economy of Viceroyalties of Nueva España and Perú and one of the main sources of income for the Spanish Crown during the XVI, XVII and XVIII centuries.

With the invention and development of the amalgamation process to treat gold and silver, mercury mining became strategically important, considering the scarcity of deposits and the great amount of ore required to supply the mines managed by the Spanish Crown in Europe and the New World, initially supplied by the Almadén mercury mine (Spain), and then also by Idrija (currently Slovenia), which helped supplying the Viceroyalty of Nueva España (Mexico) when the first one was not enough. For the particular case of Cerro Rico de Potosí, the discovery of Santa Bárbara mines in 1563 represented –because of its proximity- an essential contribution to its productivity and subsequent profitability, since it was the only productive mine in the American continent, between XVI and mid-XIX century, capable of supplying the amount of quicksilver required by Potosí and other mines, such as Porco and Oruro (currently Bolivia), Yauricocha (Cerro de Pasco), Castrovirreyna and Julcani (Huancavelica), Huarochirí (Lima), Lucanas (Ayacucho), Caylloma (Arequipa), San Antonio de Esquilache and Laycacota (Puno), Hauntajaya, Copiapó, Uspallata, Combarbala, Rancagua (Chile) among others, and it occasionally supplied the mines of the Viceroyalty of Nueva España (currently Mexico), whenever Almadén was unable to meet its demand.

The development of busconil or aludeles furnaces represented a huge advance for ore smelting process to obtain mercury, allowing a significant increase in production and supply to several silver mines in the American continent, while achieving a significant improvement in work quality and safety, as well as a significant reduction of fuel consumption (ichu), displacing old jabecas or reverberatory furnaces that were being used, thus becoming one of the world’s best technological contributions of that time in the mercury mining field. Their use was adopted in Almadén-Spain (1646) and Idrija-Slovenia by Royal Order, as well as in several minor mines in XVII and XIX centuries, such as Andacollo-Chile (1785), Punitaqui-Chile (1787), Chilapa-Mexico (1664), Chóvar/Alfondequilla-Spain (1845), San Antón/Virgen del Carmen-Spain (1888), among others, due to their great advantages.

Furthermore, Santa Bárbara mine gave place to Huancavelica city, which was initially a mining camp formed a few years after it was official founded (August 4, 1571) as Villa Rica de Oropesa in order to organize the growing community of Spanish people and indigenous workers devoted to mercury or quicksilver mining activities. This city reached an important urban development thanks to the mine richness. Such circumstance is part of the collective memory and the identity of people from Huancavelica, who recognize the relationship between the mine and the city.

The uninterrupted exploitation of the mercury mine has left several scattered testimonies of mining activities (mine openings, tailings, pits) and of ore treatment activities (smelting furnaces, slag heaps, treatment plants and associated components, etc.), as well as several buildings and structures (towns, administrative buildings, roads, bridges, channels, etc.), and the distinctive imprint of the mining landscape mainly produced by the mining and ore processing activities. All of it forms part of an indissoluble group comprised within the framework of international definitions of industrial heritage, industrial mining heritage and pre-industrial mining heritage.

Santa Bárbara mine is the most significant historical testimony of the mining network during viceregal and republican times in the current Peruvian territory (the second in the former Viceroyalty of Perú, in terms of economic significance, after Potosí silver mine, currently located in Bolivia), as well as the most significant mercury mine of the American continent, and the fourth in the world in terms of production (after Almadén-Spain, Idrija-Slovenia and Mount Amiato-Italy), and the only example of pre-industrial and industrial mining heritage of its kind (mercury or quicksilver mine) in the continent from the XVI to the XIX century. Since 2002 it has been declared as a monument part of the National Cultural Heritage (National Directorial Resolution No. 132/INC of February 28, 2002) due to its history, its economic role in the past and its relevance for mining technology development, besides its great number of structures with architectural, archaeological, artistic, urban and technological value, complemented by an astonishing natural landscape.

In definitive, only a few mining sites in Perú represent the historical significance of Santa Bárbara mine for America and Europe. It went beyond the territory of the Viceroyalty of Perú, since mercury produced was commercialized even in the more remote mines of the Andean areas and sometimes of the American continent.

The significance of Santa Bárbara started being purely economic, but it ended up gaining social and scientific relevance. First, because the mine became a place of confluence of races and cultures; second, because the interest to improve mercury mining technology promoted the exchange of technological knowledge between Spain and its American colonies, and in that field it had a great intercontinental influence with the technological contribution of aludeles furnaces, which made gold and silver processing much easier, and boosted their production.

Currently, Santa Bárbara mine comprises a wide extension of land, where several actions related to mercury mining, processing, storage and transportation were developed, promoting the rise of populations and the development of complementary management, commercial, productive, artisanal, and other activities, as well as changes in the natural landscape as a consequence of human activity, which physical and documentary testimonies are still visible. The mine site, as such, is a large and intricate network of underground galleries mined inside Santa Bárbara and Chaccllatacana mountains, between the XVI and XX (beginning) centuries, reaching a great depth. Currently, ore is no longer being extracted industrially, however it is possible to see considerable material evidence left by mining activities, developed continuously for over 400 years, in the surface and inside the mountains. This evidence is comprised by mine openings, caverns, chimneys or vents, galleries, heaps, tailings and smelting furnaces, as well as populated areas with domestic, public and religious civil architecture, roads, bridges, channels, etc., built from the XVI to XX century, among which the following stand out: Nuestra Señora de Belén galleries (1606) with its 1747 gate and San Javier (t. 1732), the Santa Bárbara populated mountain and its baroque temple (XVII century), several smelting furnaces such as San Roque, Botija Punco, Modelo, Amarupata, etc. (XVII and XVIII century), El Brocal treatment plant (first half of the XX century), among others, which exceptionally reflect the history of mining in Perú.

1. Santa Bárbara mine

According to the first Spanish chroniclers, it was considered an underground city because of the number of streets, squares and the different activities carried out therein. This statement may be confirmed with the XVII century plans that show the insides of the mine, and the existence of a complex and large circuit of galleries and caverns, where not only mercury mining activities took place, but there were also resting, worship and healthcare areas, and even an area known as coso de toros (bullfighting area). Precisely, the first bullfighting shows in the mine were presented in one of the streets called Jáuregui, and there were also five internal chapels, where religious activities were carried out. These galleries and caverns occupied a large area inside the Santa Bárbara and Chaccllatana mountains, whose subsoil hosted the underground mining activities. Currently, the entrances to the galleries are closed.

Currently two incoming mine openings stand out, the first one is called Nuestra Señora de Belen (1606), nearby the original mining camp, which access gate was carved in 1747 with the shield of Carlos III of Spain and the image of San Cristobal. It is closed due to safety reasons with iron bars and a stone wall. The other one is the San Javier mine opening, opened in the second half of the XVII century to extract ore.

Its entrance has an original stone gate with niches, which is buried for safety reasons, so only the upper part of the gate can be seen. In addition to these two entrances, there are other mine access points, which are currently closed.

2. Santa Bárbara town

The old Santa Bárbara town is currently the most complete and best preserved testimony of a mining town in the region. Its founding and/or creation date is unknown, however it should have been established in the second half of the XVI century, and it was occupied until the 1990s. Its urban features respond to its close relationship with the intense mining activity in its proximity, but differing from Huaylacucho and Sacsamarca towns, located in the mine’s periphery.

The town presents a lineal configuration oriented towards the NW-SE due to the narrow location were it has been settled. It is bordered to the west by the river and to east by the slope of Chaccllatacana mountain (inside which we find the mine’s network of galleries and caverns), and it comprises a 10 to 15 ha area with two clearly differentiated sectors for its location, design, spatial organization, and building typology. The town is accessed by a road that links the town to Huancavelica city via Sacsamarca, which is also the access to Nuestra Señora de Belén mine opening and to the contemporary treatment plant, overlapping in its last section with a road from viceregal times.

The first sector of the town comprises approximately 80% of the total area. It is located in a high area of the Chaccllatacana valley, in the right banks (East) of the river, 150 m from Nuestra Señora de Belen mine opening and at a similar height (4,249 masl). Its linear layout adapts to the land topography, and it is organized along a single road and around a wide rectangular square located in the middle of the sector, where the most important buildings –such as the parish church called Santa Bárbara, and the communal house- are located.

The church is, without a doubt, the most significant building of the Viceroyalty period in the whole area, in terms of architectonical quality, artistic features, manufacturing and scale, being a clear sample of the town’s significance in the XVII and XVIII centuries. The building date is unknown, but due to the stylistic features of its façades it seems to be from the second half of the XVII century.

It is a doctrinal church with a single rectangular nave oriented from NW to SE, with niche chapels, high chancel, sacristy, and baptistery, high choir supported by a round or Roman arch and a bell tower. It is located parallel to the square, with an atrium towards the front wall, with two of its sides defined by rustic stone walls where we find two openings with Roman arches, which serve to access a small cemetery next to the Epistle aisle and the steps that go down the mountain slope towards a stone bridge and a road built in colonial times.

It has been built with a mix of limestone masonry and irregular stone masonry with lime and sand mortar, except for the façades made of sandstone. It has a gable roof with collar beam structure made of round wood, decked ceiling with gables and harneruelo (plane formed by the collar beams) and clay roof tile cover.

On the Gospel aisle side, facing the square, it shows a singular and wide gallery or loggia (at the level of the high choir area), which is accessed through an external stone staircase located in the end that is near to the transversal wall, adjoining the wall that advances towards the square over the façade of the side entrance. The bell tower, formed by a cubic volume with a square ground plan joined to the Epistle aisle wall at the front wall level, is topped with a small dome and pinnacles at every angle.

It has two elaborated façades: the main one, located in the front wall, of Baroque style similar to the San Antonio (main) church and Santo Domingo church of Huancavelica city, and it has a recess due to the extension of the walls the bell tower and the ceiling. The side façade has a mannerist style and baroque ornaments. It is located in the Epistle aisle side and has a single body and a vertical section, where it is located the access opening with a Roman arch flanked by smooth pilasters, which entablatures support a divided triangular cleft wall crowned by a mixtilinear cornice enclosing a cross flory.

In recent years the Provincial Municipality of Huancavelica, in coordination with the Ministry of Culture, has restored almost the entire structure of the church, recovering the original figure and techniques of its composition, with the scientific accuracy required for intervention in built historic heritage.

Houses are for one family; mostly have one floor, though two-story houses are often found, mainly around the square. Houses are arranged in continuous aligned fronts, arrangement that changes towards the south, where housing units are separated from each other along the road. In general, they are manufactured with ordinary stone masonry in the first floor, with ashlar jambs and lintels, and upper walls made of adobe, which possibly correspond to further expansions of XIX and XX century. Furthermore, several one and two-story houses made entirely of adobe are observed, which are mainly located in expansion areas (the town ends and the hills). In general, the layout is not uniform, sometimes the rooms are arranged around central patios (square or rectangular) or they may be arranged in independent blocks with patios on the back, many of which present several levels because they are located in a slope. The access could be either directly or through hallways, with some examples of frontal galleries.

The second sector of the town covers approximately 20%, and it is located south of the first sector, mainly in the west bank at water-course level. In contrast to the former sector, buildings are scattered and they are arranged in one or two blocks of rooms, with wide barnyards, possibly for the packs of lamas used to transport mercury, tools and other items. All buildings are made of stone.

3. Chaclatacana buried town (Chaccllatacana)

It is currently a plateau in front of the open pit, since in the 1970s it was covered with debris removed from the open pit, after relocating the population.

The small town was comprised by several one-story houses with stone walls, covered with ichu and scattered barnyards, without a regulating layout. The main building was the chapel. It was small and had a nave with a bell tower in the Gospel aisle side.

4. Concentrating plant

It was built in the first half of the XX century. It is located near the "Belen" mine opening and Santa Bárbara town, on a roadway. The ore extracted from the open pit arrived into this plant, through a cable car system suspended by towers, which started with a cylindrical metal hopper or container that received the ore in the old Chaccllatacana town, close to the open pit entrance. Currently, the concentrating or ore treatment plant is not being used and permanent security services are provided by Sociedad Minera El Brocal S.A.A., the mine’s concession holder and owner of the plant, preserving to a large extent the integrity of structural elements, as well as the environments, levels, bridges, terraces and volumes that comprise it, most of them in regular state of conservation.

It is worth indicating that pinewood used to build the plant was purposely brought from Canada, arriving by sea into the port of Chincha and then it was taken to Huancavelica through the old mercury road Huancavelica-Chincha, to a neighborhood known as Aserradero, name that came from the activity carried out to provide wood and take it to the concentration plant. 

5. Smelting furnaces

Mining activities under the Spanish crown regime required a special infrastructure for ore processing or smelting. Thus, according to the type and environmental conditions, several processing systems were developed and/or perfected, aiming at obtaining the precious metal (gold, silver and/or mercury) destined to enriching the royal treasury, as fast and efficiently as possible, and in some cases at the lowest cost.

Huancavelica quicksilver mine is a singular case, since it was the only productive mine of its type in the American continent from the XVI to the XIX century, requiring smelting furnaces with special features that were not suitable for other types of mines, with the Almadén mercury mine (Spain) as its single reference, which transferred in the XVI century the technology used at that time: the jabecas or xabecas furnaces of Arab origin. These were commonly used in Huancavelica in the last quarter of the XVI century and the first quarter of the XVII century, until the busconil or aludeles furnace was invented, which was developed by Lope de Saavedra Barba –from Huancavelica-, and which design remained almost unaltered until the beginning of the XIX century, due to their great performance, how easy it was to build them and their low cost, despite the news of improvements made to the aludeles furnaces from Almadén (Spain) and Idrija (current Slovenia) mines. Furthermore, the implementation of a greater number of these structures was prioritized over the search of technological enhancement to increase productivity.

Based on existing descriptions and physical evidence, we know it is a cubic structure of 3 to 4 m wide by 4 to 5 m deep by 5 to 6 m high, built with ordinary stone masonry with lime and sand mortar, which hosts a central combustion chamber (furnace) or cylindrical buitron made of adobe with a 1.20 to 1.30 m diameter and of 2.50 to 3 m high approximately, which served to place cinnabar to be smelted. It has two small openings or doors covered by arches, the first of which is located in the basis of the structure’s front behind a small rectangular chamber, which served to load fuel (ichu and duff) and make fire, managed by two operators (to fan the fire and carry the fuel) in two shifts for 24 to 28 hours. The second opening is located in one of the structure’s sides, approximately 1 m over the first opening and at the grill level, with the purpose of calcining and desulphurizing ore (cinnabar) to be processed, placing in the grill a layer of already burned ore, on which the largest pieces were placed and the rest of the load was distributed in many layers according to its size and quality.

The cylindrical furnace or buitron was topped with a small semi-spherical dome (generally of adobe), which ended in a hole that was opened when fuel was being burned to prevent the fire from extinguishing, and was closed with a tile or a clay lid called canbusto, capellina or capirote, when the ore was being burned. Three clay ducts or pipes are located on the basis of the small dome, which served as vapor condensers, to which the aludeles were connected, which were clay pots opened in two sides, of 0.40 m long, 0.30 m of diameter, and 0.20 m wide in its wider part and 0.10 m wide in its narrowest part, fitted one over another and generally arranged in lines of 7 to 14 items laid on the floor with a slight downward slope, in an open backyard.

The structure was protected by an ichu cover with two slopes supported by wood beams, which only covered the furnace, and the back patio was opened, allowing an operator to cool down the aludeles with water and also to close leaks with clay. This produced vapor condensation and liquid mercury was obtained in return in the bottom of the aludeles. These were separated every two smelting cycles approximately to recover and wash mercury and ashes, repeating the same operation every day.

Furnaces could be simple or double, usually forming groups of 4 to 12 furnaces called "asientos de fundicion" (smelting sites), privately owned by the members of the Association of Miners (some of them were managed by the State) and they could be rented or transferred only among the members of such Association. Part of the smelting sites were located close to the mine galleries, where ore (cinnabar) was recovered, however there was a great number of smelting sites scattered in the plateaus and narrow valleys close to the mines, as well as in the surroundings of Huancavelica city, where ore transported from the mines by lama packs was stored and processed.

Ore recovery operations usually were conducted between December and April, and smelting operations between May and November, though such time periods were loosely followed.

6. Republican cemetery

It is located outside from Santa Bárbara town, at a lower level and in the opposite bank of the stream, next to a stone road built in viceregal times.

It has a square layout with a perimeter wall of approximately1.8 m high, which front façade oriented towards the South has an opening with a Roman arch. Inside and in the entrance axis a Miserere chapel is located. Outside, on the left side of the main front and transversal to it, a gallery-type room is located to hold the wake over of the deceased. In general it has been built with ordinary stone masonry with lime and sand mortar, and it is in good shape of preservation.

7. Mine openings

Mine openings are one of the older and more permanent testimonies. Some of them date back to the XVI century, though they might have been used until XVII and XVIII centuries. Nuestra Señora de Belén (1606) and San Javier (t. 1732) mine openings stand out because of their historical relevance and/or their (unique) gates. Nearby some of them (San Roque, Modelo, San Nicolás, Chaccllatacana, among others), it is still possible to appreciate the smelting furnaces, slag heaps, chimneys, water courses (channeled water), comprising a complex of great documentary significance, since they portray the complete process of cinnabar mining and treatment to obtain mercury.

8. Slag heaps

Slag heaps are accumulations of slag derived from mining and smelting activities, generally located in the surroundings of mine openings and smelting furnaces. Frequently it is possible to observe isolated heaps, without associated structures -since these have already disappeared- and remain as the sole testimony of their location.

Slag heaps linked to smelting furnaces are characterized for its half-moon shape almost at the foot of the structure, surrounding it partially or totally reaching 2 to 4 m of height approximately in flat or gently sloping terrain. In the case of sites with a steep slope, slag heaps are formed at the foot of the structures, generally in front of the furnace door.

Slag heaps are formed with slag from ore subject to calcination and burned ore, thus it may contain low mercury concentrations. We also find pieces of clay from discarded aludeles, pots and grills.

9. Roads

Two main roads of viceregal origin have been identified, which design and characteristics are still visible in long sections and in some isolated elements. These roads are clearly different from contemporary roads and trails that go across the entire mine and surroundings both in terms of scale and treatment. Such roads allowed communication between the mine and the city, for people to circulate (mitayos, pallaqueadores, officers, traders, traders, artisans, etc.) and to transport unprocessed ore in lama packs (destined to furnaces distributed around the city), as well as mercury distilled in smelting furnaces of the area, and inputs (tools, powder, firewood, etc.) and merchandise.

It is worth indicating that there were several minor alternate routes to transport ore from mines to smelting furnaces and populated centers, many of which have been altered or have disappeared due to the layout of 26 roads and yards for heavy machinery operation in the open pit mine site, as well as slag heaps and tailings of the XX century, among others.

One of the identified roads starts in the Sacsamarca valley, nearby the confluence of the Disparate River with the water course that flows downward across Chaccllatacana valley, then it goes up the mountain that has the same name towards Santa Bárbara town passing from one river bank to the other one in the middle of the route, crossing again a stone bridge near the town and ends with steps that arrive into the site. The second road starts in Tarapacá Street, where San Agustin mine opening is located, and goes up Botijapunco valley towards the SW to Nuestra Señora de Belen mine opening and Santa Bárbara town, with its last section corresponding to a section of the contemporary road.

Both roads have wide paved roadways, with some sections paved with cobblestone, crossed by channels and with semi-carved stone steps or steps carved into the base rock, and in some cases they were delimited by aligned semi-carved stones and/or retaining walls.

10. Bridges

Though graphic records of the end of the XVIII century point out the existence of several bridges in different points of viceregal roads, currently it is possible to identify only two testimonies (still being used) located at a short distance from each other in the proximity of the old Santa Bárbara town, over the water course of the Chaccllatacana River, which are arch structures made of irregular stone and lime and sand mortar, with no parapets or railings.

11. Channels, water courses, puquios

The mining activity and the existing towns required a permanent water supply to satisfy people’s basic needs and for the aludeles cool-down process in smelting facilities, which depended on existing puquiales (underground aqueducts) and several rivers or streams, part of which were seasonal and were sometimes channeled to ensure water distribution into remote areas.

To date it is possible to observe a great deal of evidence consisting in small sections paved with stones and/or dug in the land, as well as sequences of small ponds in the slopes of the gullies, interconnected by dug channels and fed by puquiales. Channeling works were also developed aiming at draining mine galleries due to rainwater filtrations.

12. Contemporary mine camp

Located under the treatment plant level, it is a group of buildings that dates back to the same time as the treatment plant (first half of the XX century), currently not being used and in relative good shape of preservation. The camp is comprised by 18 modules grouped in seven lines. Such modules were used for housing, service area, dinning room, recreation, etc. They are one-story buildings with stone and mud foundations and adobe walls with gable roofs and external cover. Santa Bárbara mining complex territory in Huancavelica comprises elements of different type and scale, which include geological, geographic and geomorphological aspects, landscapes, roads, mine sites, other engineering works and some civil, religious and domestic works.

13. Mining landscape

Mining activity continuously developed in Santa Bárbara mine and neighboring areas over 400 years left a mark in the natural landscape, having sensibly modified its image. Two main moments can be identified: pre-industrial mining exploitation between XVI and XIX centuries, characterized by the logging of native trees and bushes to be used as fuel in the smelting furnaces (jabecas) in XVI century and the beginning of XVII century, then moving on to using ichu as a new source of energy, and starting the production of slag heaps around the mine openings and smelting furnaces, which continued during the XVII to XIX century. The second moment, which had a larger impact, took place in the XX century with the industrial open pit exploitation, which remarkably changed the profile of Santa Bárbara mountain top and was the end of the Farallón Real (cliff), besides generating significant slag heap and tailings concentrations around such open pit due to large-scale ground shifting, therefore the natural landscape was altered as part of the historical process of both recovering and processing mining activities.

To sum up, the property proposed to be included in the World Heritage tentative list is comprised by the following areas:

Core intangible area:

 Santa Bárbara mine

 Santa Bárbara town

 Area next to the mine site, where there are several scattered smelting furnaces, slag heaps, mine openings, roads, bridges and several associated infrastructure.

 Related infrastructure of the XX century (concentrating plant, cable car system, hopper and associated structures) declared National Cultural Heritage.

 Mining landscape.

Buffering area:

 Identifiable sections of the mercury route (which also correspond to sections of the Main Andean Road or Qhapaq Ñan, which were used for land transport of ore during colonial times).

 Real state property of the Republican and contemporary period (XX century) associated to mining activities.

 Scattered smelting furnaces, slag heaps, channels, mine openings and viewpoints.

 Mining landscape.

Justification of Outstanding Universal Value

The exceptional universal value of the property subject to the proposal hereof is the result of the exchange of influences between Spain and its colonies between XVI and XIX centuries, which is expressed through the material heritage related to mercury mining, production, distribution and use along the intercontinental mercury route. For over four centuries people, knowledge, technologies and goods were shared between the Spanish crown and its American colonies, allowing the development of a mining culture around productive processes for mining, processing, transporting and trading mercury and silver.

One of America’s most significant contributions to the development of metallurgical technology was the mercury amalgamation method for gold and silver recovery. Such technique allowed metallurgical experts in Mexico and Perú to experiment and introduce technological enhancements to optimize the procedure and adapt it to the exploitation of the several silver sources located in both territories. The most significant example was the invention of the dragon or busconiles furnaces, later known as "aludeles furnaces", by the Doctor Lope Saavedra Baraba in 1633 in Huancavelica. Such technology innovations to obtain mercury were taken from America to Europe in 1646, driving mercury and silver large-scale exploitation, triggering one of the first international inflationary processes in the second hand of the XVI century. 

Santa Bárbara town and Huancavelica city are exceptional and well preserved testimonies of mining communities in the New World, where not only the urban layout and religious, civil and public buildings remain, but also the infrastructure associated to the evolution of the productive process of mercury mining and processing in colonial, republican and contemporary times. After several centuries of uninterrupted exploitation, the mine’s immediate natural environment was significantly changed. The resulting mining landscape is an exceptional testimony of human adaptation to use natural resources in a particularly hostile environment and unsuitable for the development of settlements and productive activities.

Criterion (ii): Santa Bárbara mining complex was the largest mercury producer of the New World from the XVI to the XIX century. It was an exceptional center for knowledge sharing and mining technological innovation to transform mercury distillation techniques globally, which technologically influenced quicksilver production in American and European mines from the XVIII to the XX century. Its relevance and economic and financial impact on American colonies, Spain and Europe is reflected in silver and gold production growth in the Viceroyalties of Perú and Mexico to unprecedented levels, contributing to the development of very active and independent domestic, regional and global trade channels.

The exchange of influences between Spain and its colonies between the XVI and XIX centuries is evidenced particularly through the substantial heritage related to mercury exploitation, transformation, distribution and use along the Spanish Intercontinental Royal Route. Such influences were economic, scientific, technological and cultural, among which the remarkable progress made in mercury and silver refining processes stand out. This exchange of influences expanded during republican times, which is reflected in the industrial mining complex built in the first half of the XX century to continue mercury mining activities in Santa Bárbara.

For over four centuries knowledge, technology, products and people were shared allowing developing a particular scientific culture around mercury mining, processing, transport and trading, with the corresponding projection to different fields of study. One of America’s most significant contributions to the development of the metallurgical technology was applying the amalgamation method to gold and silver refining processes.

The method called "beneficio de patio"(patio process) developed by Bartolomé de Medina in 1555 in Mexico, revolutionized the precious metal refining process, allowing the exploitation of low grade ore, which could not be exploited with the traditional smelting process. Such technique led metallurgical experts in Mexico and Perú, to experience and introduce innovative technological improvements in order to optimize the procedure and adapt it to the exploitation of several local silver sources in both territories. The invention of the heated amalgamation method, modifications introduced in jabecas furnaces, the use of powder and iron tools in mining operations and the invention of the dragon or busconil furnace –later known as "aludeles furnace" -by Lope Saavedra Barba, a Spanish doctor who lived in Huancavelica in 1633, are examples of such technological innovations.

These technological innovations for mercury recovery were taken from Huancavelica to the rest of the American continent and Europe, being adopted in Almadén-Spain (1646) by Royal Order and in Idrija-Slovenia (1752). In both places the impact of such technological innovations created in the New World was very important and it significantly contributed to the rapid rise of large-scale mercury production. Thanks to technological progress in mercury smelting and subsequent silver amalgamation, silver production reached almost industrial levels and became the basis of viceregal economy. The unprecedented growth of silver production in the Viceroyalty of Perú had a strong global impact since it triggered one of the first world’s inflationary processes in the second half of the XVI century.

On the other hand, operating needs of America’s mining economy required a great number and variety of resources and consumer goods, which promoted the development of local industries that supplied the demand of goods and services in the mine sites. Thus, mercury and silver mining generated the development of domestic markets joining large geographical areas, from Lima to the Rio de la Plata, creating very active and independent regional economic networks.

Criterion (iv): The Santa Bárbara mining complex contributes with a unique testimony of the mining technology evolution applied to cinnabar exploitation and mercury production between the XVI and XX centuries and expressed in their intensive extraction for 400 years. Santa Bárbara’s several industrial, architectonic, urban, landscape and social components illustrate the development of a mine and the towns associated to it, adapted to the territory and the most extreme environmental conditions of the Central Andes, not very suitable for life and mining industry.

Santa Bárbara mine in Huancavelica-exploited almost uninterruptedly for over 400 years- is America’s most important natural deposit of mercury during colonial times (XVI to XVIII centuries). It holds substantial evidence of undoubtedly heritage value, which show the evolution of mercury mining technology in Perú, of great significance for the success of the colonial economy based on the precious metal mining. The global economic impact produced by large exports of silver to Europe caused one of the first international inflationary crises.

Huancavelica was an essential element of the mercury route to the West, not only as a source of raw material, but also as a technological laboratory where a special technology, the dragon or busconil furnace, later known as "aludeles furnace" was developed. The introduction of the aludeles furnace, both in Europe and in the American colonies gave place to the development of a large-scale industry for mercury mining and the massive production of silver in the New World, long time before the beginning of the first Industrial Revolution in the UK.

Civil and religious architecture built outside the mine during viceregal times has been preserved with a significant degree of integrity and authenticity, and there are several buildings of a remarkable testimonial value. Santa Bárbara town and Huancavelica city are the best examples of mining settlement planning, adapted to extreme climate and topographic conditions of the Central Andes of Perú during colonial times. Furthermore, they are exceptional testimonies of mining communities in the New World, where not only the houses, churches, urban layout and other social spaces remain, but also infrastructure associated to the evolution of the productive process of mercury mining and refining, from the XVI century to the first half of the XX century.

Moreover, the mercury refining plant, built during the first half of the XX century by the businessman Eulogio Fernandini de la Quintana, was one of the most advanced of that time in South America. Pinewood was used to build it, brought by seas exclusively from Canada, and machinery was specially acquired in Europe and then adapted to the difficult environment of Huancavelica, including a small hydroelectric power plant and a small railway for ore transportation. The abundant mining infrastructure of that time is an exceptional testimony of the continuity of a large tradition of mining technology innovations in Perú.

After centuries of uninterrupted exploitation and processing of cinnabar to obtain mercury, the mine’s immediate natural environment changed significantly. The resulting mining landscape is an exceptional testimony of human adaptation to use natural resources in a particularly hostile environment, unsuitable for the development of settlements and productive activities (4.200 masl). The change from a mining industry based on plentiful labor, comprised by indigenous mitayos, to another one based on knowledge and technology of the XX century can be easily understood due to the numerous industrial and urban material remains scattered in the immediate landscape of Santa Bárbara mine, both in its core area and its buffer zone.

In the second half of the XX century this interaction was more direct, since the topography of a sector of the historical core’s surroundings changed because the exploitation system changed from underground to open-pit mining, evidencing mercury-mining technology in a specific period of time. Its great relevance is in the fact that it was the only mercury mine in the entire American continent, until the California mines were discovered in the mid-XX century.

Statements of authenticity and/or integrity

Authenticity of natural and cultural elements that comprise the site proposed is present in the location and in Santa Bárbara mining complex.

Huancavelica city, underground works (caverns, galleries) carried out in Santa Bárbara and Chaclatacana mountains in the intersection with the Gran Farallón, as well as ore processing (smelting) facilities, services and housing facilities scattered in nearby mountains and valleys, and mining facilities of the XX century, are evidence of the use and human adaptation to a hostile environment such as the high Peruvian Central Andes, over 4,100 masl, uninterruptedly for over four centuries. The concurrence of a successful adaptation to the environment and the local development and improvement of silver amalgamation techniques using mercury made Huancavelica an important center of technology innovation and quicksilver production, which was destined to Cerro Rico de Potosí mine and other mines in the American continent.

Huancavelica mining landscape preserves numerous elements that were part of the productive process of the mercury mining industry. The high degree of authenticity preserved by such elements allows clearly reading the historical process that made Santa Bárbara one of the most significant places for the successful development of the viceregal economy.

The economic development of Huancavelica based on the mercury industry, was responsible for the creation of regional integration networks in the southern Andes, which are still operating to date despite the breakdown of economic and commercial dynamics supporting such integration. The hard living conditions of miners and several ways of forced labor (mining mita) have produced throughout its history specific expressions of a culture with distinctive features currently emerging in behaviors, religious beliefs, oral expressions, traditions and music. The present community of Santa Bárbara greatly portrays this living cultural manifestation, since it maintains and preserves many of the ancestral traditions related to the mining activity that even today are passed to new generations.

The spirit of Santa Bárbara mine, as an old mining center of transnational relevance is recognized even today, both due to the current cultural landscape modified after four centuries of transformations, as well as to subsisting material evidence of viceregal, republican and contemporary times.

Over four hundred years have passed since -with the arrival of the Spaniards- Santa Bárbara mine started exploiting mercury at a large scale. During that time, the mine was expanded and became progressively deeper in order to follow the ore veins. Inside the mine domestic spaces, streets, plazas and chapels that were used by miners remain, as evidenced in historical plans and descriptions of the XVIII century. Currently, the mine openings are sealed, thus it is not possible to verify the current state of preservation of internal structures. Notwithstanding the entrance gates 36 of Belen and San Javier galleries remain, the latter of which is covered with slag.

Integrity

Though currently Santa Bárbara is not being used, its urban layout remains intact. It is comprised by narrow streets and a wide square, as well as a great part of one and two-story houses, and public buildings including the baroque church devoted to Santa Bárbara, which was recently restored (the only structure that is currently being used), and the cemetery, which allows a perfect understanding of urban life of mining societies in that time.

Mining facilities -built during the first half of the XX century- were destined to the exploitation of the Chaccllatacana Mountain, next to Santa Bárbara town. Such contemporary facilities represent a historical period of mercury exploitation and processing, thus they are now integral part of the site and are in good shape of preservation. The current concession holder is Sociedad El Brocal S.A.A., which is no longer conducting mining activities in the area since 1975, and it holds the facilities that have been declared National Cultural Heritage in 2008.

Comparison with other similar properties

In Perú, there are many cities of viceregal origin, which historical centers are National Cultural Heritage. Some of these cities were founded based on the development of mining activities, but in no case the material testimonies of such industrial heritage have been included in the Cultural Heritage Declaration, and thus they have no legal protection. Industrial heritage of the XX century is in a similar situation. Huancavelica and Santa Bárbara mine are the first case in which we aim at protecting both viceregal evidence of mining production and Republican and contemporary industrial heritage, mainly because Santa Bárbara is one of the few cases where original evidence of these historical periods is so completely preserved. 

Santa Bárbara mine and UNESCO global strategy

As part of the UNESCO global strategy, ICOMOS prepared a study to identify the cultural heritage categories underrepresented both in the World Heritage List and in the Tentative List of State Parties ("Filling the Gaps: An Action Plan for the Future". ICOMOS, 2005). As a result of that study, several typologies were prepared to classify the World Heritage, in order to identify those categories that are underrepresented in the List. Such categories were grouped in three non-exclusive classification frameworks:

1. Typological classification

2. Chronological-regional classification

3. Thematic classification

Through there are many sites with industrial mining heritage recorded in the World Heritage List, Huancavelica mines represent the case of a few mines in the world related with mercury mining and refining, none of which has yet been included in the World Heritage List. On the other hand, Huancavelica mines have three main chronological components: viceregal, republican and contemporary, thus the property could be included on more than one heritage category.

Within the framework of the Typological Classification, Huancavelica mines are within two main categories: "agricultural, industrial and technological properties" and "modern heritage". Latin American and the Caribbean region are underrepresented in both categories.

Within the framework of the Chronological-Regional Classification, Huancavelica mines fit in two categories: "Colonial State in South America" and "Development of Independent States until World War I". The first category is one of the best represented in the case of Latin America. The second one only had one case in 2005: the Port of Valparaiso in Chile. 38

Within the framework of the Thematic Classification, Huancavelica would classify in the category "Creative responses and Continuity", and at the same time in the sub-categories: "industrial architecture", "uninhabited urban settlement" and "industrial landscape". It also classifies in the category "utilization of natural resources", and in the sub-category "Mining and quarries".

Therefore, Santa Bárbara inclusion in the World Heritage Tentative List is fully justified since it is a distinctive site for several categories of heritage that are underrepresented in the World Heritage List.

At a regional and global level, Huancavelica may be compared with other sites, which according to the abovementioned ICOMOS study, correspond to the following thematic categories: "Colonial States in South America", "Development of Independent States until World War I", "Modern Heritage" and "Agricultural, Industrial and Technological Properties".

At the regional level, the contemporary industrial mining heritage of Huancavelica is comparable to the Sewell mining town and the Humberstone and Santa Laura saltpeter works in Chile, while the testimonies of viceregal times are comparable to the historic town of Guanajuato and adjacent mines, and to the historic center of Zacatecas, both in Mexico, and to the city of Potosí in Bolivia.

It is worth mentioning that the most similar properties to Huancavelica are the mercury mines of Almadén (Spain) and Idria (Slovenia), both recorded in the World Heritage List. Once included in the Tentative List, Santa Bárbara mine could apply to be part of a cultural tour together with the abovementioned properties.