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.
Description
Very good aggregate of highly lustrous sphalerite crystals, with amber–ruby internal translucence ("Ruby Jack"). Stepped growths of sharp faces, compact habit, set on a small carbonate matrix on the back (serving as a support).
History of this specimen
Ex S. Müller collection, with the original typewritten label of Jeffrey Mining Co., Inc., a company associated with the mineral trade in Tennessee. Regular production at Elmwood began in 1975, and Jeffrey Mining Co. is documented in the mineral trade by at least 1991. The specimen can therefore be provisionally placed between those dates, although its exact year of extraction remains unknown.
About Esfalerita
Sphalerite is the principal ore of zinc and one of the most studied species for its variable iron content, which modifies colour and lustre. Elmwood varieties, with amber to ruby tones and high lustre, are among the most highly regarded worldwide.
About the locality
Elmwood is a world-class classic mine for sphalerite, calcite and barite, in shared or separate parageneses. Although it reopened after more than 30 years closed due to the low profitability of zinc and worked with miners to place good collector specimens on the market, the mine closed for good on 31 December 2023. Much good material came out, but no more will.
Technical data
- Catalogue No.
- 0161
- 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
- Size (cm)
- 9.5 x 7.7 x 4.8
- Weight
- 421 g
- Ex-collection
- S. Müller
- Etymology
- From the Greek "sphaleros" (σφαλερός), meaning 'deceptive' or 'treacherous'. It was named for its resemblance to galena, the principal lead ore, yet it yields no lead, frustrating miners in antiquity.
- Quality
- Notable
- Value trend
- Al alza
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