Orange brown crystals of Gottlobite (Picture size: 1.5 mm) Locality: Glücksstern Mine, Gottlob, Friedrichroda, Thuringia, Germany — Photo: Thomas Witzke · CC BY-SA 3.0 de
Gottlobite
An orange-to-brown calcium-magnesium vanadate-arsenate of the adelite group, forming half-millimetre crystals.
Intro adapted from Wikipedia (CC BY-SA).
Gottlobite is an IMA-recognized mineral species in the vanadate class, with the chemical formula CaMg(VO₄)(OH).
It crystallizes in the orthorhombic crystal system (space group P2_12_12_1). It is a member of the Adelite structural group.
Key properties: Mohs hardness 4.5; specific gravity 3.31; Light brown streak; Vitreous to adamantine luster; optically biaxial.
IMA symbol Got, IMA status: approved, named in 1998.
From hydrothermal baryte veins.
It is found associated with Hausmannite, baryte, adelite, wakefieldite-(La).
The name refers to the occurrence in Germany at Gottlob hill.