Madre de Dios Mine
Encyclopedia
Máfil
Máfil is a town and commune of the Valdivia Province, Los Ríos Region in southern Chile, about 30 km northeast of Valdivia...
in Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
, is a placer deposit
Placer deposit
In geology, a placer deposit or placer is an accumulation of valuable minerals formed by gravity separation during sedimentary processes. The name is from the Spanish word placer, meaning "alluvial sand". Placer mining is an important source of gold, and was the main technique used in the early...
of gold
Gold
Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...
that has been mined several times since its discovery in 1556. The bedrock
Bedrock
In stratigraphy, bedrock is the native consolidated rock underlying the surface of a terrestrial planet, usually the Earth. Above the bedrock is usually an area of broken and weathered unconsolidated rock in the basal subsoil...
of the Madre de Dios area is made of metamorphic and crystalline rocks of Paleozoic
Paleozoic
The Paleozoic era is the earliest of three geologic eras of the Phanerozoic eon, spanning from roughly...
age all part of the Bahía Mansa Metamorphic Complex
Bahía Mansa Metamorphic Complex
The Bahía Mansa Metamorphic Complex or BMMC is a group of metamorphic geologic formations of the Chilean Coast Range in southern Chile. It consists mainly in pelitic schists, metagreywackes and oceanic type mafic metavolcanics....
. These rocks are covered with thick layers of glacial gravel
Gravel
Gravel is composed of unconsolidated rock fragments that have a general particle size range and include size classes from granule- to boulder-sized fragments. Gravel can be sub-categorized into granule and cobble...
from the Tertiary
Tertiary
The Tertiary is a deprecated term for a geologic period 65 million to 2.6 million years ago. The Tertiary covered the time span between the superseded Secondary period and the Quaternary...
. Gold eroded from the gravel have deposited in nearby streams, thus giving origin to the placer deposit. The deposit was discovered by Spaniards in 1556 but was not mined extensivelly until the late 19th century.
From 1898 to 1936 a total of 2,6 tonne
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...
s of gold were produced. The deposits are currently being by prospected Global Gold corporation.
Sources
39°36′34"S 72°46′15"W