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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 2025.

Esfalerita Cleiofana o Blenda acaramelada from Las Mánforas, Áliva, Camaleño, Cantabria, España — Terrium

Description

Gem-quality "caramel" sphalerite. Translucent gem-quality sphalerite crystal, with intense caramel colour and reddish, honey and orange reflections in transmitted light. Shows a complex habit, with well-defined edges, minimal contact area and no damage. Strong vitreous lustre and full volume, with exceptional presence for the locality.

History of this specimen

I see it as an uncut gem. One of those pieces that define what "caramel sphalerite" really means when Áliva is discussed. It has its own entry on FMF https://www.foro-minerales.com/forum/download.php?id=107211

About Esfalerita

Sphalerite is the principal zinc mineral. At Áliva it may occur as opaque masses or, exceptionally, as translucent crystals in honey, amber or deep red tones. These gem-quality cleiophanes are the aesthetic pinnacle of the locality and are very scarce.

About the locality

The Áliva mines, in the Picos de Europa, now closed, are celebrated for their "caramel" sphalerite. Also called Las Mánforas, a name derived from the concession "La Almanzora", they attracted little interest for centuries: only hand-picked galena was collected to glaze pottery, and the harsh environment made exploitation almost impossible. The altitude limited work to June–October because of snow and extreme weather. After industrialisation, in the 1970s more than 600,000 tonnes of ore were extracted. They closed for good in the late 1990s.

Technical data

Catalogue No.
0041
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)
3 x 3 x 2
Weight
28 g
Acquired
2025
Ex-collection
Diego Navarro
Etymology
From the Greek "sphaleros", "deceptive", for its resemblance to galena. It is the principal ore mineral of zinc.
Quality
Notable
Value trend
Al alza

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