Crocoite comes from Tasmania and is the National Mineral

Crocoite comes from Tasmania and is the National Mineral – a place it justly deserves.

Crocoite is a beautiful mineral and we have some new pieces in the shop.

Some of the Crocoite shows the continuing process of formation. We have several that have Crocoite needles covered in Gibbsite (brown mineral) and then Dundasite (white mineral) and finally you can see new Crocoite mineral forming on top. 

The formation of these Crocoite minerals is fascinating. Initially Lead Chromate crystals PbCrO4 – in solution, formsCrocoite. When these chemicals were exhausted, the mineral Gibbsite (brown mineral) forms over the Crocoite.Then finally, when the Gibbsite is exhausted the mineral Dundasite (white mineral) forms. Finally more PbCrO4 creates more needles of Crocoite. (This can be seen as the new needles form at 90 degrees to the first formations of Crocoite.)

Crocoite has a Mohs Hardness of 2.5 – 3
Specific Gravity of 5.9 – 6.1

It has a monoclinic crystal system.

  • June 6, 2017