Home Mineralia Specimens Locations Sitio en Español English Site
Santa Fé, Guanajuato, Mexico
From the time of the Colonial Settlers the mining potential of Mexico was well understood and the development of silver mines in different areas was not only a priority for them and the Spanish Crown, as a means of raising funds for further explorations and maintaining the colonies, but as a new type of mining which was highly lucrative. Guanajuato, since the very beginning, was always one of the major sites. So much so that for more than 400 years it has been an important producer of silver for the international market. Its fame surpassed the frontiers of America and became recognized in all of Europe. Its production was so magnificent that between 1781 and 1800, Guanajuato provided 64% of all the silver extracted worldwide.
The mining district of Guanajuato is located to the northeast of Mexico City, in the centre of the state that bears the same name, Guanajuato. The area where the lode of silver is mined, about 20 kilometres long, a location known of since the Spanish settlers arrived. The southern parts of this territory were the empires of the Chichimecas, natives who paid homage to the Aztecs. In 1529, Nuño de Guzmán conquered this region. In 1548, the mining potential of the region was recognized by the discovery of Juan Rayas of the Veta Madre de Guanajuato, known today as La Mina de Rayas. By 1558, several mines were in operation in the area; this gave rise to the growth of the city. The city was given the official title of ‘The Loyal and Noble Town of Santa Fe Guanajuato’.
Mining owes its success to a change of method that revolutionized the exploitation of mines in Mexico: THE COURTYARD SYSTEM. This system was created in 1555, in the town of Pachuca by Bartolome de Medina. It is quite likely that he took the idea from the book by Agricola ‘De Re metallic in which a similar technique is described. It was based on an empirical process of amalgamation and destruction of the extracted rocks, pulverized by a series of ‘arrastras’ (drags), which are enormous wheel shaped stones, rolled over the extracted rock, pulled by mules. The ‘dust’ was then mixed with salt, iron, copper sulphate, lemon, and vegetable ash to amalgamate the gold or silver when mercury was added. Next the solution would be heated until the mercury evaporated and the pure precious metal was left behind, ready to be smelted. The process was elaborated in large courtyards or patios in the exterior areas of the mines. Although, this process is based on chemical formulas, at the time it was not clearly understood how it worked. It totally revolutionized the industry, but it also had some problems, the salts, the mercury and the iron all had to be imported from Europe. These elements were so important to the process that they became the motive of conflict. The Spanish-Austrian Crown wanted to take control of the area of Europe where these elements came from, an area that aspired to gain independence for religious reasons and eventually the Thirty Year War broke out.The mining boom was so great that its economic success is still evident today in the colonial buildings. The cathedral, its palaces and governmental headquarters reflect the opulence of their Spanish owners. It is not surprising that in 1810, when the social revolution began, not only were the local natives but the first revolutionary attacks directed towards Guanajuato. This was the perfect example of the class differences of the period.


The attack was the near downfall of Guanajuato as a mining town, as the insurgents burned and totally destroyed all of the mines. In 1823, when Mexico gained independence from Spain, an effort was made to revive the mining zone, this was achieved by accepting financing and allowing foreign companies, primarily British, to join forces. However, it was not until the mid nineteenth century that the productivity was restored. With the arrival of new techniques, especially the introduction of the steam engine, the industry experienced an unimaginable improvement. This continued until the beginning of the twentieth century, but on account of the unacceptable working conditions for the miners, many accidents and even deaths occurred and the prosperity of the mines began to decline. The Mexican Revolution practically destroyed the industry and it was not until 1935 that, with the influx of North American capital, production was once again restored. Social changes, the introduction of co-operatives and new investors, have continued changing throughout the history of this region, but even today the region offers an important production from its epithermal veins by way of by products such as lead, zinc and copper. In the absence of precise facts, it has been estimated that more than 30 million tons of silver and 124,000 tons of gold have been extracted from the mines of Guanajuato.