Schlegelite
Schlegelite is an IMA-recognized mineral species in the arsenate class, with the chemical formula Bi₇O₄(MoO₄)₂(AsO₄)₃.
It crystallizes in the orthorhombic crystal system (space group Pnca).
Key properties: Mohs hardness 3.5; specific gravity 7.23; Pale yellow streak; Adamantine luster; optically biaxial.
IMA symbol Scg, IMA status: approved, named in 2003.
Occurs as crystal masses in vugs in quartz, formed either in an oxygenated weathering or oxygenated hydrothermal environment.
It is found associated with Quartz, petitjeanite, pucherite, bismuth, sillenite.
The mineral was named to honor Fritz Schlegel (b. 1938), a dedicated mineral collector and finder of the new species, for his contributions to the mineralogy of the Schneeberg area, Saxony, Germany.