Esfalerita
Esfalerita is a mineral with formula (Zn,Fe)S, in the Sulfuros group. This specimen comes from Elmwood Mine, Carthage, Smith County, Tennessee, Estados Unidos and joined the Terrium collection in 2001.
Description
Very dark brown, lustrous sphalerite crystals with well-defined faces and reflective surfaces. A pale, arched, elongate calcite aggregate grows over them, forming a curved loop over the piece. Small but very aesthetic group.
About Esfalerita
Sphalerite is the principal zinc ore mineral and can show very dark colours when it contains iron. It commonly occurs with calcite and dolomite in hydrothermal sulphide deposits.
About the locality
Elmwood is a classic, world-class mine for sphalerite, calcite and baryte, both in shared and separate parageneses. The best specimens came from its classic period, when operations allowed pieces to reach the market through the miners themselves. In 2010 Nyrstar reopened it after more than thirty years closed owing to the low profitability of zinc, but prohibited the extraction of specimens and threatened immediate dismissal for anyone who did so. It closed permanently on 31 December 2023. Elmwood produced much, very good material, but no more will come out.
Technical data
- Catalogue No.
- 0373
- Composition
- (Zn,Fe)S
- Name
- Esfalerita
- Group
- Sulfuros
- Category
- Cupidium
- Associations
- calcita, dolomita
- Mine
- Elmwood Mine
- District / Municipality
- Carthage
- Province
- Smith County
- Region
- Tennessee
- Country
- Estados Unidos
- Acquired
- 2001
- Ex-collection
- Domingo Moreno (Txomín)
- Etymology
- From the Greek "sphaleros" (σφαλερός), meaning 'deceptive' or 'treacherous'. It was so named for its resemblance to galena, the principal ore of lead, yet it yielded no lead, to the frustration of ancient miners.
- Quality
- Muy buena
- Value trend
- Al alza
Related specimens
- Acantita (Paramórfica tras Argentita) — Marruecos
- Analcima — Estados Unidos
- Auricalcita — Estados Unidos
- Boltwoodita — Estados Unidos
- Calcita (Ahumada) — Estados Unidos
- Calcita — Estados Unidos
- Calcita — Estados Unidos
- Calcopirita (Irisada) — Francia