Mroseite , Tellurite Locality: Moctezuma Mine (Bambolla Mine), Moctezuma , Municipio de Moctezuma , Sonora , Mexico ( Locality at mindat.org ) Size: 10.7 x 7.6 x 4.0 cm. This large specimen features numerous fat tellurite crystal clusters to 5-6mm perched on the edges of a protected vug, lined with drusy quartz - a beautiful and unusually rich specimen. This piece is also rich in the rarer species Mroseite, which is present as white cleavage fragments all over the left-hand side of the specimen (per Bill Pinch, Mark Feinglos, and Marcus Origlieri by visual inspection). One of the surprises of 2007 for rarities was the reworking of the famous old Bambolla mine in the Moctezuma tellurium complex for specimens, by several European-led collecting teams. Many specimens were then sold at Munich 2008 and this year in Tucson. — Photo: Robert M. Lavinsky · CC BY-SA 3.0
Mroseite
Mroseite is an IMA-recognized mineral species in the carbonate class, with the chemical formula CaTe⁴⁺O₂(CO₃).
It crystallizes in the orthorhombic crystal system (space group Pbca).
Key properties: Mohs hardness 4; specific gravity 4.35; White streak; Adamantine luster; optically biaxial.
IMA symbol Mros, IMA status: approved, named in 1974.
Very rare in a hydrothermal Au–Te deposit (Moctezuma mine, Mexico).
It is found associated with Spiroffite, tellurium, tellurite, denningite, zemannite, quartz (Moctezuma mine, Mexico); oboyerite, choloalite, gold (Tombstone, Arizona, USA).
The mineral was named to honor Mary Emma Mrose (1910–2003), American mineralogist, U.S. Geological Survey, Washington, D.C.