Kurnakovite Value, Price, and Jewelry Information

Rob Lavinsky, iRocks.com – CC-BY-SA-3.0 [CC-BY-SA-3.0], via Wikimedia Commons

Kurnakovite

Kurnakovite is similar to inderite. Both are colorless and very uninteresting as faceted gems, which is why very few have been cut. The material is obtainable in large size, but softness and cleavage make cutting a real chore.

Kurnakovite Information

Data Value
Name Kurnakovite
Is a Variety of Inderite
Colors Colorless, with a white surface coating.
Crystallography Triclinic. Crystals large and blocky, often in clusters; large cleavable masses; aggregates.
Refractive Index 1.488-1.525
Luster Vitreous.
Hardness 2.5-3
Fracture Conchoidal
Specific Gravity 1.78-1.85
Birefringence 0.027-0.036.
Cleavage Good 1 direction
Stone Sizes California material could yield stones of several hundred carats from large transparent masses or cleavages.
Luminescence None.
Luminescence Present No
Transparency Translucent to transparent.
Absorption Spectrum Not diagnostic.
Formula

Mg2B611 · 15H2O.

Pleochroism

None.

Optics

a = 1.488-1.491 ; β = 1.508-1.511;  γ = 1.515-1.525. Biaxial (+), 2V= 80°.

Optic Sign Biaxial +

Optics: a = 1.488-1.491 ; β= 1.508-1.511;  γ= 1.515-1.525.

Biaxial (+), 2V= 80°.

Occurrence: Borate deposits in arid areas.

Inder Lake. Kazakhstan.

Boron, Kern County California: crystals to 24 inches across and large masses.

Comments: Kurnakovite is similar to inderite. Both are colorless and very uninteresting as faceted gems, which is why very few have been cut. The material is obtainable in large size, but softness and cleavage make cutting a real chore.

Name: After N. S. Kurnakov, Russian mineralogist and chemist.