Analcima
Analcima is a mineral with formula NaAlSi₂O₆·H₂O, in the Zeolitas group. This specimen comes from Cairns Bay, Flinders, Mornington Peninsula Shire, Victoria, Australia and joined the Terrium collection in 2000.
Description
Rounded, trapezohedral, translucent, lustrous crystals, well formed, growing in a cavity of dark basaltic matrix, with excellent definition and high crystal quality.
History of this specimen
I got it from an old Italian systematic collection mainly focused on zeolites. The original collector collected it himself at Flinders, Australia; it was in his register as no. 3100, and in 2000 he valued it at 75,000 lire (c. €38).
About Analcima
Analcime is a hydrated sodium aluminosilicate, a member of the zeolite group. It crystallises as pseudocubic trapezohedra and typically forms in cavities of volcanic rocks.
About the locality
Flinders, on the Mornington Peninsula, is known for basaltic cavities with highly transparent trapezohedral analcime.
Technical data
- Catalogue No.
- 0114
- Composition
- NaAlSi₂O₆·H₂O
- Name
- Analcima
- Group
- Zeolitas
- Category
- Cavella
- Matrix
- Roca volcánica oscura (basalto)
- Mine
- Cairns Bay
- District / Municipality
- Flinders
- Province
- Mornington Peninsula Shire
- Region
- Victoria
- Country
- Australia
- Size (cm)
- 6 x 5 x 3.5
- Weight
- 94.1 g
- Acquired
- 2000
- Ex-collection
- Coleccionista italiano
- Etymology
- From the Greek "ἀναλκιμος" ("analkimos"), meaning "weak", in reference to its low electrostatic charge when rubbed.
- Quality
- Muy buena
- Value trend
- Estable