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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 1994.

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

Description

Single translucent orange crystal with amber and golden tones, very strong adamantine lustre and notable internal fire. Well-defined faces and light-catching surfaces, typical of the Áliva caramel sphalerites.

History of this specimen

It comes from Óscar's former collection; he bought it as a youngster in 1994 for under 200 pesetas—a symbol of another era and of how accessible these specimens were then. For me it is also a reminder of that time. Today, after the definitive closure of the workings, its value has increased markedly.

About Esfalerita

Sphalerite is a zinc sulphide that crystallises in the cubic system and may show tetrahedral and dodecahedral forms. The caramel-coloured variety from Áliva stands out for its transparency, adamantine lustre and warm tones, due to traces of cadmium and other metals.

About the locality

The Áliva mines, in the Picos de Europa, now closed, are renowned for their "caramel" sphalerite. Also called Las Manforas, a name derived from the "La Almanzora" concession. For centuries they attracted little interest: only galena was hand-picked to glaze ceramics, and the harsh environment made exploitation almost impossible. 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.

Technical data

Catalogue No.
0115
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
26 g
Acquired
1994
Ex-collection
Óscar Herranz
Etymology
From the Greek "sphaleros" ("deceptive"), in reference to its frequent confusion with galena.
Quality
Buena
Value trend
Al alza

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