Boron - Kern County California, USA — Photo: Pacific Museum of Earth from Canada · CC BY-SA 2.0
Kurnakovite
A hydrated magnesium borate — the triclinic dimorph of inderite.
Intro adapted from Wikipedia (CC BY-SA).
Kurnakovite is an IMA-recognized mineral species in the oxides & hydroxide class, with the chemical formula MgB₃O₃(OH)₅·5H₂O.
It crystallizes in the triclinic crystal system (space group P-1).
Key properties: Mohs hardness 2.5–3; specific gravity 1.85–1.86; typically white or colorless; Vitreous luster; refractive index 1.506; optically biaxial.
IMA symbol Kko, grandfathered status — known before the IMA’s founding, named in 1940.
An uncommon mineral, typically in lake-bed borate deposits.
It is found associated with Szaibelyite (Lake Inder, Kazakhstan).
The mineral was named to honor Professor Nikolai Semenovich Kurnakov (1860-1941), Russian mineralogist and chemist, Institute of General and Inorganic Chemistry, Moscow, Russia.
Collections: Collector Favorites, Rare & Remarkable.