Jouravskite Locality: N'Chwaning Mines, Kuruman , Kalahari manganese fields, Northern Cape Province , South Africa ( Locality at mindat.org ) Size: 7 x 3.5 x 1.3 cm. A resplendent specimen of an incredibly rich coating of the very rare species Jouravskite. The carpet of gemmy yellow microcrystals (up to 1 mm) covers much of the matrix on the presentation side. Ex. Charlie Key. — Photo: Robert M. Lavinsky · CC BY-SA 3.0
Jouravskite
Jouravskite is an IMA-recognized mineral species in the sulfate class, with the chemical formula Ca₃Mn⁴⁺(SO₄)(CO₃)(OH)₆·12H₂O.
It crystallizes in the hexagonal crystal system (space group P6_3). It is a member of the Ettringite structural group.
Key properties: Mohs hardness 2.5; specific gravity 1.81–1.95; [Vitreous.] luster; optically uniaxial.
IMA symbol Jou, IMA status: approved, named in 1965.
Rare in the oxidized portions of manganese deposits; an aluminian variety formed by the action of volcanic fumaroles.
It is found associated with Manganite, calcite, marokite, gaudefroyite, henritermierite, despujolsite, barite (Tachgagalt, Morocco).
The mineral was named to honor Georges Jouravsky (1896–1964), Chief Geologist, Geological Survey of Morocco, for his work on the mineral deposits of Morocco.