Esfalerita
Esfalerita is a mineral with formula ZnS, in the Sulfuros group. This specimen comes from Mina Troya, Mutiloa, Gipuzkoa, Euskadi, España and joined the Terrium collection in 2010.
Description
Sphalerite cabinet specimen dominated by superficial dolomite. Both minerals show good crystallization, creating a sharp contrast of white and brown foam-like aggregates. Fine splashes of pyrite-chalcopyrite are scattered across the piece, visible with a field loupe.
History of this specimen
This was piece #1420 from the Aleydis Soliveres collection, and it still retains the inventory number written in black over white correction fluid. It perfectly showcases the classic aesthetic of the Mutiloa district: tabular white dolomite paired with warm-toned zinc and lead sulfides.
About Esfalerita
The primary zinc ore and a major sulfide, mined at Áliva alongside galena and pyrite. Its color dictates its iron content—darkening as iron increases—and is also influenced by trace elements like mercury, copper, or bismuth.
About the locality
A historic European reference locality. Worked by Exminesa between 1986 and 1993, when a collapse forced its closure. It was an underground lead-zinc mine with more than a kilometre of workings. Its large geodes, some of several cubic metres, produced some of Spain's best sphalerites, prized for their transparency and honey-cognac colour. Closed and flooded since 2009, today only the tailings pond remains.
Technical data
- Catalogue No.
- 0036
- Composition
- ZnS
- Name
- Esfalerita
- Group
- Sulfuros
- Category
- Cupidium
- Matrix
- Roca oscura
- Associations
- dolomita cuarzo pirita
- Mine
- Mina Troya
- District / Municipality
- Mutiloa
- Province
- Gipuzkoa
- Region
- Euskadi
- Country
- España
- Size (cm)
- 9.5 x 6 x 4.5
- Weight
- 310 g
- Acquired
- 2010
- Ex-collection
- Aleydis Soliveres
- Etymology
- From the German "Blende", meaning "deception", because of its resemblance to galena despite containing no lead.
- Quality
- Muy buena
- Value trend
- Al alza
Related specimens
- Abellaíta — España
- Abernathyita — España
- Abernathyita — España
- Abernathyita — España
- Acantita (Paramórfica tras Argentita) — Marruecos
- Aerenita — España
- Aerinita (fibrosa) — España
- Analcima — España