TERRIUM — A mineralogy cabinet

Eritrina

Eritrina is a mineral with formula Co₃(AsO₄)₂·8H₂O, in the Arseniatos group. This specimen comes from Distrito de Bou Azzer, Bou Azzer, Ouarzazate, Drâa-Tafilalet, Marruecos.

Eritrina from Distrito de Bou Azzer, Bou Azzer, Ouarzazate, Drâa-Tafilalet, Marruecos — Terrium

Description

Aggregates of pink erythrite crystals with small quartz crystals on matrix in a fissure vug. Aesthetic in hand and under the loupe.

About Eritrina

Erythrite is a cobalt arsenate easily recognizable by its intense pink to magenta color. It forms as a secondary mineral in the oxidation zones of cobalt-bearing deposits, almost always originating from the oxidation of skutterudite. It crystallizes in radial or prismatic aggregates. It is brittle, with variable luster, and is highly prized for its aesthetic appeal. In this specimen, two generations can be observed: well-defined prismatic crystals and more compact spherulites. For miners, finding erythrite on the surface was definitive proof that a valuable deposit of cobalt, nickel, or silver was hidden right underneath.

About the locality

The Bou Azzer district, Morocco, is the best-known erythrite locality worldwide. Active since the early 20th century, it continues to yield high-quality specimens. Its geological conditions favour associations with quartz, scorodite and roselite. Specimens with well-defined crystals and saturated colour, like this one, are highly collectable.

Technical data

Catalogue No.
0053
Composition
Co₃(AsO₄)₂·8H₂O
Name
Eritrina
Group
Arseniatos
Category
Cavella
Associations
Cuarzo
Mine
Distrito de Bou Azzer
District / Municipality
Bou Azzer
Province
Ouarzazate
Region
Drâa-Tafilalet
Country
Marruecos
Size (cm)
5 x 4 x 3
Weight
65.2 g
Etymology
From the Greek "eruthrós" ('red'), in reference to its characteristic colour.
Quality
Buena
Value trend
Al alza

Related specimens

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