Esfalerita Cleiofana o Blenda acaramelada
Esfalerita is a mineral with formula ZnS, in the Sulfuros group. This specimen comes from Las Mánforas, Áliva, Camaleño, Cantabria, España and joined the Terrium collection in 2000.
Description
Massive triangular fragment with very good cleavage, showing sharp faces. Stands out for colour, transparency and form. Bright lustre and a strong amber tone.
History of this specimen
I gave it to Óscar because it was his favourite mineral. When I bought it, I still did not know how to tell crystallised sphalerite from a cleaved mass. In fact, it took me quite a while to understand the difference. Now, with a bit of attention, I spot it at a glance.
About Esfalerita
Sphalerite (or blende) is the principal ore mineral of zinc and one of the best-known sulphides. At Áliva it was mined together with galena and pyrite. Colour variations are mainly linked to iron content—the higher the content, the darker the tones—but also to trace elements such as mercury, copper or even bismuth.
About the locality
Áliva, in the Picos de Europa, is a classic Spanish sphalerite locality because it produced a very recognisable honey-amber sphalerite, appreciated in Spain and abroad for its transparency and honey-amber tones. The Las Mánforas complex—its name popularly derived from "La Almanzora"—worked mostly zinc and lead ores in a harsh setting, with seasonal operation due to snow, altitude and climate. After centuries of limited activity, the mine reached industrial scale in the 20th century, exceeded 600,000 tonnes extracted in the 1970s, and closed in 1989. The last collector pieces came out in 1993.
Technical data
- Catalogue No.
- 0002
- Composition
- ZnS
- Name
- Esfalerita
- Variety
- Cleiofana o Blenda acaramelada
- Group
- Sulfuros
- Category
- Cupidium
- Mine
- Las Mánforas
- District / Municipality
- Áliva
- Province
- Camaleño
- Region
- Cantabria
- Country
- España
- Size (cm)
- 6.5 x 5 x 5
- Weight
- 230 g
- Acquired
- 2000
- Ex-collection
- Domingo Moreno (Txomín)
- Etymology
- From the Greek "sphaleros" (σφαλερός), meaning 'deceptive' or 'treacherous'. It was so named because of its resemblance to galena, the principal lead ore, yet yielding no lead—much to the frustration of ancient miners.
- Quality
- Notable
- 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