Eritrina Acicular
Eritrina is a mineral with formula Co₃(AsO₄)₂·8H₂O, in the Arseniatos group. This specimen comes from Agoudal, Bou Azzer, Ouarzazate, Drâa-Tafilalet, Marruecos and joined the Terrium collection in 2025.
Description
Magenta tufts on an earthy matrix; velvety appearance, subdued lustre.
History of this specimen
Marcos guided me so I would not let that large specimen slip away; it is now worth more than double.
About Eritrina
Acicular erythrite, or cobalt bloom, is a hydrated cobalt arsenate that commonly occurs in bright pink to violet colours. This acicular variety is less common than the classic tabular habit. It forms velvety botryoidal aggregates, like those in this specimen, with a silky aspect and homogeneous coverage. It is an excellent visual indicator of the presence of cobalt in a deposit.
About the locality
Bou Azzer is the only mining district in the world where cobalt has been mined as the principal ore. Erythrites from this area are distinguished by their vivid colouration, multiple crystal habits, and associations with other arsenates. Although it remains in limited production, specimens with well-defined aesthetics are increasingly sought after.
Technical data
- Catalogue No.
- 0054
- Composition
- Co₃(AsO₄)₂·8H₂O
- Name
- Eritrina
- Variety
- Acicular
- Group
- Arseniatos
- Category
- Asteris Explosio
- Matrix
- Matriz terrosa
- Mine
- Agoudal
- District / Municipality
- Bou Azzer
- Province
- Ouarzazate
- Region
- Drâa-Tafilalet
- Country
- Marruecos
- Size (cm)
- 5 x 4 x 3
- Acquired
- 2025
- Ex-collection
- Marcos López (Ponferrada)
- Etymology
- From the Greek "eruthrós" ("red"), in reference to its characteristic colour.
- 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