FOV 2.4 x 2.9 mm. Found August 1997. MOB coll. This specimen was confirmed at the Canadian Museum of Nature. See http://www.mindat.org/photo-166788.html for more information. The color is more orange than red. But it is impossible to visually distinguish khomyakovite from manganokhomyakovite, ferrokentbrooksite or other eudialyte group members at MSH. The environment is igneous breccia rather than a miarolitic cavity. From: Poudrette quarry, Mont Saint-Hilaire, La Vallée-du-Richelieu RCM, Montérégie, Québec, Canada. — Photo: Modris Baum · CC0
Khomyakovite
An exceedingly rare eudialyte-group mineral with tungsten in its complex formula.
Intro adapted from Wikipedia (CC BY-SA).
Khomyakovite is an IMA-recognized mineral species in the silicate class, with the chemical formula Na₁₂Sr₃Ca₆Fe₃Zr₃W(Si₂₅O₇₃)(O,OH,H₂O)₃(Cl,OH)₂.
It crystallizes in the hexagonal crystal system (space group R3m). It is a member of the Eudialyte structural group.
Key properties: Mohs hardness 5–6; specific gravity 3.14; White streak; Vitreous luster; optically uniaxial.
IMA symbol Kmy, IMA status: approved, named in 1998.
Found in miarolitic cavities in nepheline syenite in an alkaline intrusive complex.
It is found associated with Analcime, annite, calcite, natrolite, pyrite, titanite.
The mineral was named to honor Dr. Alexander Petrovich Khomyakov (b. 1933), of the Institute of Mineralogy, Geochemistry and Crystal Chemistry of Rare Elements, Moscow, Russia.