Mineral Species: Gypsum and Glauberite

Chemical Formula: CaSO4-2(H2O) and Na2Ca(SO4)2

Chemical Name: Hydrated Calcium Sulfate and Sodium Calcium Sulfate

Mineral Class: Sulphates

Mineral Notes: Glauberite is a mineral known better for when it is not there rather than its presence. The reason is that it is readily pseudomorphed by other minerals which adopt its original shape and crystal habit. Probably the main reason for this behaviour is its water solubility. It dissolves leaving a cast of itself filled in by other minerals. One of the most common replacements is by Gypsum, a closely related, but less soluble mineral.

Description: A specimen consisting mostly of Gypsum replacing Glabuerite, but the pseudomorphism is only partial. Therefore some Glauberite remains and can be seen by its darker reddish colour. A nice combination of minerals.

Location: Camp Verde, Arizona, USA.