Ettringite - Wessels Mine, South Africa

Top 10 Amethyst Countries Map - EarthWonders Newsletter #8

specimen
Ettringite
SpeciesSize
Comments
Details
ColorsYellow
SizeSmall
Dimensions6.9 x 4.9 x 1.1 cm
Species
Description
The rare mineral ettringite (Hydrated Calcium Aluminum Sulfate Hydroxide), closely related to sturmanite, is well-known in specimens from the Wessels locality. It forms as a precipitate from hydrothermal solutions. This is a plate of bright yellow, solid ettringite, crystallized on the surface with the typical nailhead-form crystals.
Origin