The Peñasquito Polymetallic Mine is the fifth largest silver mine in the world and the second largest in Mexico. It is located in north-eastern corner of the State of Zacatecas and is wholly owned by

Newmont Goldcorp Newmont Corporation is a gold mining company based in Greenwood Village, Colorado, United States. It is the world's largest gold mining corporation. Incorporated in 1921, it owns gold mines in Nevada, Colorado, Ontario, Quebec, Mexico, the Domin ...

. It is an

open pit Open-pit mining, also known as open-cast or open-cut mining and in larger contexts mega-mining, is a surface mining technique of extracting rock or minerals from the earth from an open-air pit, sometimes known as a borrow. This form of minin ...

operation which began operations in March 2010, but still managed to produce 13,952,600 ounces of

silver Silver is a chemical element with the symbol Ag (from the Latin ', derived from the Proto-Indo-European ''h₂erǵ'': "shiny" or "white") and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical ...

that year. Estimated reserves for the Peñasquito Mine are 17.82 million oz of

gold Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile me ...

, 1,070.1 million oz of silver, 3,214 tons of

lead Lead is a chemical element with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cu ...

and 7,098 million tons of

zinc Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodi ...

. The mine has its own radio station, XHESP-FM 98.9 "Radio Peñasco".

Geology

The country rock consists of

Mesozoic The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretace ...

sediments that were deposited in the

Basin of Mexico The Valley of Mexico ( es, Valle de México) is a highlands plateau in central Mexico roughly coterminous with present-day Mexico City and the eastern half of the State of Mexico. Surrounded by mountains and volcanoes, the Valley of Mexico wa ...

(Mexico Geosyncline). These sediments were intruded by quartz-feldspar porphyries,

quartz monzonite Quartz monzonite is an intrusive, felsic, igneous rock that has an approximately equal proportion of orthoclase and plagioclase feldspars. It is typically a light colored phaneritic (coarse-grained) to porphyritic granitic rock. The plagiocl ...

porphyries, and other feldspar-phyric intrusives in the late

Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...

to the mid- Oligocene, which form sills,

dikes Dyke (UK) or dike (US) may refer to: General uses * Dyke (slang), a slang word meaning "lesbian" * Dike (geology), a subvertical sheet-like intrusion of magma or sediment * Dike (mythology), ''Dikē'', the Greek goddess of moral justice * Dikes ...

, and stocks. The primary ore for the Peñasquito Polymetallic Mine is in two

diatreme A diatreme, sometimes known as a maar-diatreme volcano, is a volcanic pipe formed by a gaseous explosion. When magma rises up through a crack in Earth's crust and makes contact with a shallow body of groundwater, rapid expansion of heated wate ...

breccia Breccia () is a rock composed of large angular broken fragments of minerals or rocks cemented together by a fine-grained matrix. The word has its origins in the Italian language, in which it means "rubble". A breccia may have a variety of ...

s, named the Peñasco and the Brecha Azul. The mineralization contains gold, silver, lead and zinc. The

s flare upward, and are filled with

ted country rock and intrusions. The rock surrounding the diatremes contain disseminated galena, sphalerite and

sulfosalt Sulfosalt minerals are sulfide minerals with the general formula , where *A represents a metal such as copper, lead, silver, iron, and rarely mercury, zinc, vanadium *B usually represents semi-metal such as arsenic, antimony, bismuth, and rarely ...

s within phyllic (

sericite Sericite is the name given to very fine, ragged grains and aggregates of white (colourless) micas, typically made of muscovite, illite, or paragonite. Sericite is produced by the alteration of orthoclase or plagioclase feldspars in areas that hav ...

–

pyrite The mineral pyrite (), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Fe S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral. Pyrite's metallic luster and pale brass-yellow hue giv ...

–

quartz Quartz is a hard, crystalline mineral composed of silica ( silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical ...

) and proplytic ( chlorite–

epidote Epidote is a calcium aluminium iron sorosilicate mineral. Description Well developed crystals of epidote, Ca2Al2(Fe3+;Al)(SiO4)(Si2O7)O(OH), crystallizing in the monoclinic system, are of frequent occurrence: they are commonly prismatic in hab ...

–pyrite)

hydrothermal alteration Metasomatism (from the Greek μετά ''metá'' "change" and σῶμα ''sôma'' "body") is the chemical alteration of a rock by hydrothermal and other fluids. It is the replacement of one rock by another of different mineralogical and chemical co ...

envelopes. Where the diatremes intersect

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

units manto deposits of ore mineralization occur.

2017 Protest

A week-long protest disrupted operations at the Peñasquito mine during the first week of October 2017.

Goldcorp Goldcorp Inc. was a gold production company headquartered in Vancouver, British Columbia, Canada. The company employed about 15,800 people worldwide, engaged in gold mining and related activities including exploration, extraction, processing and ...

had been forced to "announce a temporary suspension of operations due to a blockade by truck drivers protesting a loss of contracts at the country’s biggest gold deposit."

References

Silver mines in Mexico Gold mines in Mexico Surface mines in Mexico Geology of Mexico {{mining-stub