Pink microcrystals of burckhardtite, an extremely rare tellurium mineral from Moctezuma, that is the type locality and only one of the few localities known worldwide (Moctezuma Mine, Moctezuma, Moctezuma Municipality, Sonora, Mexico). — Photo: David Hospital · CC BY-SA 4.0
Burckhardtite
Burckhardtite is an IMA-recognized mineral species in the silicate class, with the chemical formula Pb₂(Fe³⁺Te⁶⁺)(AlSi₃O₈)O₆.
It crystallizes in the hexagonal crystal system (space group P-31m).
Key properties: Mohs hardness 2; specific gravity 4.96; Pale red streak; Adamantine to slightly pearly luster; optically biaxial.
IMA symbol Bkd, IMA status: approved, named in 1976.
Found in a breccia, loosely cemented by dickite, in very thin disseminations on quartz fragments.
It is found associated with Moctezumite, zemannite, tellurite, barite, dickite, quartz.
The mineral was named to honor Mexican geologist Carlos Burckhardt (1869–1935).