Afghanita
Afghanita is a mineral with formula (Na,K)₂₆Ca₁₄[Si₂₄Al₂₄O₉₆](CO₃)₆(SO₄)₆Cl₆·2H₂O, in the Silicatos (Tectosilicatos) group. This specimen comes from Ladjuar Medam, Sar-e-Sang, Kuran wa Munjan District, Badakhshan, Afganistán.
Description
Two small, well-formed blue afghanite crystals showing strong orange fluorescence under ultraviolet light.
About Afghanita
Afghanite is an extremely complex tectosilicate of the cancrinite group. Although it can be visually confused with lazurite or sodalite, it is distinguished by its hexagonal prismatic habit and by a composition that includes carbonate, sulphate and chloride anions. Its most distinctive feature is its intense orange fluorescence under ultraviolet light.
About the locality
Type locality for afghanite. Sar-e-Sang, in Badakhshan, is one of the world’s most important historic mineralogical regions, known for more than 6,000 years for lapis lazuli mining. Afghanite occurs associated with these bodies, forming in marble skarns by contact metamorphism. The material comes from very specific zones of the deposit and is scarce relative to the dominant lazurite. Specimens with good blue colour and intense fluorescence, like this, are sought by collectors because they are from the type locality.
Technical data
- Catalogue No.
- 0630
- Internal reference
- X0341
- Composition
- (Na,K)₂₆Ca₁₄[Si₂₄Al₂₄O₉₆](CO₃)₆(SO₄)₆Cl₆·2H₂O
- Name
- Afghanita
- Group
- Silicatos (Tectosilicatos)
- Category
- Meritum Persé
- Mine
- Ladjuar Medam
- District / Municipality
- Sar-e-Sang
- Province
- Kuran wa Munjan District
- Region
- Badakhshan
- Country
- Afganistán
- Etymology
- Named in 1968 for its discovery locality, Badakhshan Province, Afghanistan.
- Quality
- Buena
- Value trend
- Estable