earthstory: Ettringite Rare and fragile, the beautiful…
Ettringite
Rare and fragile, the beautiful hexagonal crystal (4 x 2.1 x 1.2 cm) in the photo comes from the only source of this gemmy yellow sulphate mineral: The N’Chwaning Mines in South Africa?s Kalahari manganese fields. Elsewhere it occurs as microcrystals, usually white to colourless. The mineral needs careful storage, since it is hydrated, and as water evaporates from the structure the colour turns white.
This entry was posted in Beautiful Minerals. Bookmark the permalink.