Carlfriesite Locality: Moctezuma Mine (Bambolla Mine), Moctezuma , Municipio de Moctezuma , Sonora , Mexico ( Locality at mindat.org ) Picture width 2 mm. Collection and photograph Christian Rewitzer — Photo: Christian Rewitzer · CC BY-SA 3.0
Carlfriesite
A rare yellow calcium tellurate- tellurite mineral named for mineral collector Carl Fries Jr.
Intro adapted from Wikipedia (CC BY-SA).
Carlfriesite is an IMA-recognized mineral species in the oxides & hydroxide class, with the chemical formula CaTe⁴⁺₂Te⁶⁺O₈.
It crystallizes in the monoclinic crystal system (space group C2/c).
Key properties: Mohs hardness 3.5; specific gravity 6.3; Very pale yellow streak; optically biaxial.
IMA symbol Clf, IMA status: approved, named in 1973.
Found in cavities in an oxidized hydrothermal Au–Te deposit in intensely silicified brecciated rhyolite vitrophyre.
It is found associated with Cerussite, chlorargyrite, argentian gold, cesbronite, calcite, dickite, barite, bornite, galena, hessite.
The mineral was named to honor Carl Fries, Jr. (1910–1965), U.S. Geological Survey and the Geological Institute of the National University, Mexico City, Mexico.