Property Description

San Juan de Nepomuceno, Cadereyta de Montes, Querétaro

Rich silver deposits were discovered by Spanish Conquistadors around the year 1557 in the mountain range known as El Doctor giving rise to the community San Antonio del Doctor in the state of Queretaro and in 1728, the San Juan Nepomuceno mine entered into production. From that date till the War of Independence in 1810, the Doctor became one of the principal producers of silver in the country. The mine has been placed in production on several occasions by different companies over the last 100 years, but is currently inactive. The San Juan Nepomuceno Mine is considered one of the richest historic mines in Mexico with silver grades of more than half a kilo per ton.

The property consists of 6 concessions covering an area of 544.5092 Hectares. There is excellent access with roads, water, electrical power and basic services in the community of El Doctor located on the property. A smelter is 5 kilometers away in the town of Maconí.

The mineralization is in the form of chimneys, veins and mantos and is made up of oxides and sulphides of silver, lead, zinc, copper, mercury, and antimony hosted by limestone of the El Doctor Formation. There are professional reports with metallurgical studies and reserve calculations based on sampling of existing workings. The property has not been explored with modern methods and there exists excellent potential for discovery of additional economic reserves.


Reports and Presentations


The property may be reached by a 2.5 hours drive from the city of Querétaro along paved roads with year-round access.

Local Infrastucture

  • Water may be obtained from a spring located 2.0 km from the mine entrance. There is sufficient flow year-round to operate a small flotation plant.
  • Electricity is available on the property from high tension electric cables. It will be necessary to install a substation.
  • Fuel, lodging, restaurants, communication services are available in San Joaquín, located 8 km NNE of the mine.

Geological Setting

The local geology consists of Upper Jurassic – Lower Cretaceous shales and limestones of the Trancas, Doctor and Soyatal-Mezcala Formations. The Trancas Formation is Upper Jurassic in age and is composed of carbonaceous shales, shaley limestones, greywackes and sands. The Doctor Formation of Lower Cretaceous age overlies the Trancas Unit and is composed of grey, microcrystalline limestone in the area of the mine. The Soyatal-Mezcala Formation overlies the Doctor Formation and is composed mostly of reddish-brown calcareous clays which have been altered into skarns in some areas where affected by granitic intrusions.


All the mine workings occur in the grey, microcrystalline limestone of the Doctor Formation. Oxides occur near the surface with sulphide mineralization at depth.

Potential Size and Grade

According to a 1989 report by the Consejo de Recursos Minerales (see attached document), a rough calculation of reserves was determined at 55,200 tons with grades of 0.73 gpt Au and 592 gpt Ag. This calculation was made based on observations from the accesible levels of the mine. There is exploration potential for more mineralized bodies in the vicinity.

Exploration History

San Juan de Nepomuceno was first mined in 1557 by Spanish Conquistadores. In 1870, Victor Beaurang obtained the mining concessions and installed the first cooling furnace in Maconí. In the 1930's, the English company O.J. Braniff installed a smelter and transported ore from the mine by mule carts. In 1951, the Compañía Minera Esmeralda, S.A. processed ore from San Nepomuceno for about 2 years. The mine lay dormant until 1978 when Mr. Marín Torres Herrera installed a flotation plant to process sulphide ore and equipped the mine with electricity, water, ventilation, and winch to permit access to the lower levels of the mine.

General Specs

San Juan de Nepomuceno, Cadereyta de Montes, Querétaro

Commodities: Ag-Au-Pb-Zn-Cu-Sb-Hg
Deposit Type: Polymetallic Replacement Deposit
State: Querétaro
Municipality: Cadereyta de Montes
Surface Area: 544.5092 Ha
Type Of Deal: Sale or Option
Go to Location: Lat: 20.843 Lon: -99.588
Kmz File:


Name: Ing. Douglas Coleman
Phone: +52-1 (662) 181-0189
Email: [email protected]



Name Title No. Document
Ampliación a San Juan Nepomuceno 214456
San Juan Nepomuceno 170052
San Juan 5 229627
San Juan 4 211604
San Juan 2 214737
San Juan 3 215327




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