Crocoita
Crocoita is a mineral with formula PbCrO₄, in the Cromatos group. This specimen comes from Adelaide Mine, Dundas, Zeehan, Tasmania, Australia.
Description
Spherical aggregate with internal red acicular crystals. This piece shows sharp, tooth-like, well-defined crystals, typical of the Dundas locality. Invites hand-lens inspection.
About Crocoita
Crocoite is a lead chromate known for its intense red-orange colour and elongated prismatic crystals. It is brittle, with vitreous lustre, and usually forms in cavities of metamorphic rocks where chromium and lead are present.
About the locality
The Adelaide mine in Dundas (Tasmania) is the classic locality for crocoite, but the value of this specimen lies in the fact that it was extracted by hand by local miner Shane Schreiber. He is well known on the circuit for his skill in retrieving these crystals intact from the rock with minimal damage. Finding a pocket with such sharp and brilliant specimens today is increasingly difficult, as the richest areas of the deposit are nearly exhausted and what comes out is usually very coarse. Towards the end of the 19th century, Dundas experienced a boom as a silver mining town (lead and argentiferous galena). The first prospectors and miners arrived there in the 1880s. At one point, the population reached 1,081 census-registered people, only 76 of whom were women.
Technical data
- Catalogue No.
- 0055
- Composition
- PbCrO₄
- Name
- Crocoita
- Group
- Cromatos
- Category
- Cavella
- Matrix
- Matriz terrosa limonítica
- Mine
- Adelaide Mine
- District / Municipality
- Dundas
- Province
- Zeehan
- Region
- Tasmania
- Country
- Australia
- Size (cm)
- 5 x 3.5 x 2.5
- Weight
- 41.8 g
- Ex-collection
- Shane Schreiber
- Etymology
- The name "crocoite" comes from the Greek krokos (κρόκος), meaning "saffron", in reference to its red-orange colour similar to the stigma of that flower. It was first described in the 18th century, and its chemical formula is PbCrO₄ (lead chromate).
- Quality
- Buena
- Value trend
- Estable