Knorringite
A magnesium-chromium garnet discovered in 1968 in Lesotho's Kao kimberlite — a tracer mineral for diamond-bearing kimberlites.
Intro adapted from Wikipedia (CC BY-SA).
Knorringite is an IMA-recognized mineral species in the silicate class, with the chemical formula Mg₃Cr₂(SiO₄)₃.
It crystallizes in the cubic crystal system (space group Ia-3d). It is a member of the Garnet structural group.
Key properties: Mohs hardness 7; specific gravity 3.756; Vitreous luster.
IMA symbol Krr, IMA status: approved, named in 1968.
A rare component of ultramafic kimberlite nodules (Kao kimberlite pipe, Lesotho).
It is found associated with Olivine, enstatite, chromian diopside, chromian pyrope, chromian spinel, ilmenite, perovskite, zircon, diamond, omphacite, rutile, carbonates.
The mineral was named to honor Dr. Oleg von Knorring (1915–1994), Department of Earth Sciences, Leeds University, Leeds, England.