Heulandita
Heulandita is a mineral with formula (Ca,Na)₂-₃Al₃(Al,Si)₂Si₁₃O₃₆·12H₂O, in the Silicatos (Tectosilicatos) group. This specimen comes from Canteras de Nashik, Nashik, Maharashtra, India and joined the Terrium collection in 2024.
Description
Well-formed prismatic crystal of slightly bluish heulandite, growing in a chalcedony-lined cavity on brown volcanic matrix. Dark microcrystals lining the geode provide contrast and depth. The arrangement of the crystal and cavity produces a curious pareidolia effect, evoking the silhouette of an animal head.
About Heulandita
Heulandite is a tectosilicate of the zeolite group, common in geodes within basalts and other volcanic rocks. Its rhombohedral crystals and short prismatic habit allow it to be distinguished from closely related species such as stilbite or clinoptilolite.
About the locality
Nashik Quarries.
Technical data
- Catalogue No.
- 0160
- Composition
- (Ca,Na)₂-₃Al₃(Al,Si)₂Si₁₃O₃₆·12H₂O
- Name
- Heulandita
- Group
- Silicatos (Tectosilicatos)
- Category
- Cavella
- Matrix
- Calcedonia
- Mine
- Canteras de Nashik
- District / Municipality
- Nashik
- Region
- Maharashtra
- Country
- India
- Size (cm)
- 60 x 40 x 30
- Weight
- 72 g
- Acquired
- 2024
- Etymology
- Named in honour of the British mineralogist and dealer Henry Heuland (1778-1856).
- Quality
- Muy buena
- Value trend
- Estable