Okenita
Okenita is a mineral with formula Ca₅Si₉O₂₃·9H₂O, in the Filosilicatos group. This specimen comes from Malad Quarry, Mumbai Suburban District, Konkan, Maharashtra, India.
Description
Single, minute spherical aggregate of white acicular crystals with cottony appearance and silky lustre, on matrix.
History of this specimen
This is an specimen from the classic Malad Quarry in Mumbai, now closed. A locality famed for cavities in the Deccan basalts, where okenite formed with zeolites and prehnite.
About Okenita
It resembles a ball of cotton wool, but it is made of thousands of very fragile microscopic needles. It is a secondary mineral occurring in cavities of volcanic rocks, especially in the Deccan basalts of India. Okenite forms at low temperature under specific conditions of moisture and internal chemistry. Its delicate appearance contrasts with the harsh environment in which it forms, and specimens are much prized by collectors.
About the locality
For decades the basalt cavities at Malad yielded fine okenite specimens. The quarry is now closed, and available pieces come from old material, so they are increasingly valued.
Technical data
- Catalogue No.
- 0420
- Internal reference
- T0027
- Composition
- Ca₅Si₉O₂₃·9H₂O
- Name
- Okenita
- Group
- Filosilicatos
- Category
- Asteris Explosio
- Mine
- Malad Quarry
- District / Municipality
- Mumbai Suburban District
- Province
- Konkan
- Region
- Maharashtra
- Country
- India
- Size (cm)
- 1 x 1 x 1
- Weight
- 4.5 g
- Etymology
- Okenite is named in honour of the German naturalist Lorenz Oken (1779–1851) for his contribution to nineteenth-century science. It was first described in 1828.
- Quality
- Buena
- Value trend
- Estable
Related specimens
- Antigorita — España
- Antigorita (serpentinita) — España
- Apofilita — India
- Calcita (Melada) — India
- Cavansita — India
- Calcedonia Estalactítica — India
- Calcedonia Estalactítica — India
- Calcedonia Estalactítica — India