Seeligerite Locality: San Francisco Mine (Beatrix Mine), Caracoles , Sierra Gorda District, Tocopilla Province , Antofagasta Region , Chile ( Locality at mindat.org ) Field of view 7 mm. Specimen and photo Leon Hupperichs. — Photo: Leon Hupperichs · CC BY-SA 3.0
Seeligerite
A rare yellow lead chloride-iodate — dense (SG 6.8) from its lead content.
Intro adapted from Wikipedia (CC BY-SA).
Seeligerite is an IMA-recognized mineral species in the iodate class, with the chemical formula Pb₃(IO₄)Cl₃.
It crystallizes in the orthorhombic crystal system (space group Cmm2).
Key properties: specific gravity 6.83; optically biaxial.
IMA symbol Sli, IMA status: approved, named in 1970.
A rare secondary mineral formed in the oxidized zone of hydrothermal polymetallic mineral deposits.
It is found associated with Boleite, paralaurionite, schwartzembergite (Santa Ana mine, Chile).
The mineral was named to honor Erich Seeliger, Professor of Mineralogy, Technical University, Berlin, Germany.