Mercurio
Mercurio is a mineral with formula Hg, in the Sulfuros group. This specimen comes from Mina de Almadén, Almadén, Ciudad Real, Castilla-La Mancha, España and joined the Terrium collection in 2025.
Description
Specimen of massive cinnabar with elongated, tower-like form. To the naked eye it shows a dark matt red with metallic zoning and no evident crystals. Under the loupe, numerous bright microdroplets of native mercury and small, intensely red crystals are dispersed over the surface.
About Mercurio
Cinnabar is mercury sulphide and its principal ore. Under supergene conditions (in contact with the surface), part of the mineral may alter (because the sulphur dissolves), releasing metallic mercury, mobilising it and causing it to precipitate again as visible microdroplets on the surface. The coexistence of massive cinnabar, microcrystals and native mercury in a single specimen illustrates, exceptionally, the geochemistry of mercury in oxidising environments. It is also the mineral from which the pigment known as vermilion was obtained. Mercury retains the symbol Hg from Hydrargyrum, "liquid silver". And in English, quicksilver.
About the locality
Almadén is the largest natural mercury anomaly on the planet and for almost two millennia was its principal producer. From the 16th century, in coordination with Idrija, it was decisive for American silver: mercury crossed the Atlantic bound for Potosí and Zacatecas because without mercury there was no amalgamation, without amalgamation there was no silver, and without silver the imperial currency could not be sustained. But the human cost was immense. Miners and prisoners worked exposed to highly toxic vapours, to the point that in 1773 the Royal Mining Hospital of San Rafael was established, considered the world's first hospital specialised in occupational diseases. Although the mine always belonged to the Crown, its management and commercialisation passed at different times to major European financial houses, first the Fuggers and later the Rothschilds, who would also come to control Idrija. Later, during the Second Republic, in 1937, the coup leader General Franco bombed Almadén to deprive the Republic of a strategic resource. That same mercury inspired Alexander Calder's Mercury Fountain in the Spanish pavilion in Paris, which was exhibited next to Picasso's Guernica. The mine closed definitively in 2003 and today, together with Idrija, forms part of the UNESCO World Heritage.
Technical data
- Catalogue No.
- 0319
- Composition
- Hg
- Name
- Mercurio
- Group
- Sulfuros
- Category
- Meritum Persé
- Matrix
- Cinabrio
- Mine
- Mina de Almadén
- District / Municipality
- Almadén
- Province
- Ciudad Real
- Region
- Castilla-La Mancha
- Country
- España
- Size (cm)
- 7 x 3 x 2.5
- Acquired
- 2025
- Ex-collection
- Amelia Molina
- Etymology
- From the Greek "kinnábari" and the Latin "cinnabaris", the ancient name of the mineral. The symbol Hg comes from "hydrargyrum", "liquid silver".
- Quality
- Buena
- Value trend
- Al alza
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