Roselita
Roselita is a mineral with formula Ca₂Co(AsO₄)₂·2H₂O, in the Arseniatos group. This specimen comes from Distrito de Bou Azzer, Tazenakht, Ouarzazate, Drâa-Tafilalet, Marruecos.
Description
Deep cavity lined with fuchsia to wine-red roselite crystals. Crystals in radial sheaves. Excellent condition, no damage or fractures.
About Roselita
Roselite is a hydrated calcium–cobalt arsenate, valued for its intense pink–fuchsia colour. At Bou Azzer it occurs as well-formed crystals with highly saturated colour and associations that have made the locality a classic reference for the species. It represents the cobalt-rich end-member of the roselite–wendwilsonite series: the two minerals share the same crystal structure but differ in the dominant cation, cobalt in roselite and magnesium in wendwilsonite.
About the locality
The Bou Azzer mining district is one of the world's best known localities for cobalt minerals. Its geodes rich in arsenic minerals such as roselite, erythrite or skutterudite are prized worldwide.
Technical data
- Catalogue No.
- 0085
- Composition
- Ca₂Co(AsO₄)₂·2H₂O
- Name
- Roselita
- Group
- Arseniatos
- Category
- Cavella
- Mine
- Distrito de Bou Azzer
- District / Municipality
- Tazenakht
- Province
- Ouarzazate
- Region
- Drâa-Tafilalet
- Country
- Marruecos
- Size (cm)
- 7 x 5 x 4
- Weight
- 108.2 g
- Ex-collection
- Diego Navarro
- Etymology
- Named in honour of the German mineralogist Gustav Rose.
- Quality
- Muy buena
- Value trend
- Al alza
Related specimens
- Abernathyita — España
- Abernathyita — España
- Abernathyita — España
- Acantita (Paramórfica tras Argentita) — Marruecos
- Adamita — México
- Adamita — México
- Adamita (Cuprífera) — Grecia
- Adamita — México