Estaurolita
Estaurolita is a mineral with formula Fe2+2Al9Si4O23(OH), in the Silicatos group. This specimen comes from Antananolofotsy, Andrembesoa, Betafo District, Vakinankaratra, Madagascar.
Description
Floater thumbnail with a complete cruciform staurolite twin. Dark brown crystals with well-proportioned arms, sharp angles and a matte lustre. Very clean, recognisable geometry.
About Estaurolita
Staurolite is a silicate from aluminium-rich metamorphic rocks, especially schists and gneisses. Its cruciform twins are one of the most recognisable habits in classical mineralogy, which makes them very popular with collectors. Their cross shape has also given them a certain religious and esoteric symbolism.
About the locality
These metamorphic terrains lie in the central highlands and they are a classic Madagascan locality for twinned staurolite.
Technical data
- Catalogue No.
- 0692
- Composition
- Fe2+2Al9Si4O23(OH)
- Name
- Estaurolita
- Group
- Silicatos
- Category
- Meritum Persé
- Mine
- Antananolofotsy
- District / Municipality
- Andrembesoa
- Province
- Betafo District
- Region
- Vakinankaratra
- Country
- Madagascar
- Size (cm)
- 2 x 2 x 1.5
- Weight
- 9.1 g
- Ex-collection
- Miguel Ángel Amaya Riejos
- Etymology
- From the Greek «staurós», meaning «cross», in reference to the species' characteristic cruciform twins.
- Quality
- Notable
- Value trend
- Estable
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