Schmiederite Locality: El Dragón mine, Antonio Quijarro Province , Potosí Department , Bolivia ( Locality at mindat.org ) Picture width 2 mm. Collection and photograph Christian Rewitzer — Photo: Christian Rewitzer · CC BY-SA 3.0
Schmiederite
A secondary lead-copper selenite-selenate described in 1962 from Argentina's Cóndor mine.
Intro adapted from Wikipedia (CC BY-SA).
Schmiederite is an IMA-recognized mineral species in the oxides & hydroxide class, with the chemical formula Cu₂Pb₂(Se⁴⁺O₃)(Se⁶⁺O₄)(OH)₄.
It crystallizes in the monoclinic crystal system (space group P2_1/m). It is a member of the Linarite structural group.
Key properties: specific gravity 5.62; Subadamantine, satiny in aggregates luster; refractive index 1.943; optically biaxial.
IMA symbol Scm, grandfathered status — known before the IMA’s founding, named in 1962.
A rare secondary mineral found in the oxidized zone of selenium-bearing hydrothermal base metal deposits.
It is found associated with Chalcomenite, molybdomenite, umangite, clausthalite (Cóndor mine, Argentina).
The mineral was named to honor Oscar Schmieder (1891–1980), German geographer, a Director of the Museum of Mineralogy and Geology, National University, Córdoba, Argentina.