Kyanite Value, Price, and Jewelry Information
Kyanite is very rare as a faceted gem, especially if free from inclusions and flaws. The material is extremely difficult to cut because of its perfect cleavage and the extreme variability in hardness in different directions in the same crystal. A few catseye kyanites are known to exist.
Kyanite is very rare as a faceted gem, especially if free from inclusions and flaws. The material is extremely difficult to cut because of its perfect cleavage and the extreme variability in hardness in different directions in the same crystal. A few catseye kyanites are known to exist.
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for full access to our price guide (updated monthly).Kyanite Value
Trimorphous with Andalusite, Sillimanite.
Optics: a = 1.710-1.718; β = 1.721-1.723; γ= 1.727-1.734.
Cr-kyanite: a = 1.714; β= 1.724; γ= 1.731; birefringence = 0.017; S.G.=3.67 birefringence = 0.017: S.G. = 3.67.
a = 1.720;,β= 1.730; γ= 1.753; birefringence = 0.033; S.G. = 3.70.
Biaxial ( - ), 2V= 82-83°.
Occurrence: in schists, gneiss, and granite pegmatites. Many localities are known.
Various places in the United States, especially Yancy County, North Carolina: deep blue or green crystals, up to 2 inches long, some facetable.
Vermont; Connecticut; Virginia; Georgia; Massachusetts. Mozambique: dark blue, with Cr and Ti.
India; Italy.
Brazil: large blue and blue-green crystals.
Machakos District, Kenya: large blue crystals, banded with green; also colorless!
Switzerland: with staurolite in schist.
Kenya: fine blue color, facetable.
Comments: Kyanite is very rare as a faceted gem, especially if free from inclusions and flaws. The material is extremely difficult to cut because of its perfect cleavage and the extreme variability in hardness in different directions in the same crystal. A few catseye kyanites are known to exist.
Name: From the Greek kyanos, meaning blue.
Joel E. Arem, Ph.D., FGA
Dr. Joel E. Arem has more than 60 years of experience in the world of gems and minerals. After obtaining his Ph.D. in Mineralogy from Harvard University, he has published numerous books that are still among the most widely used references and guidebooks on crystals, gems and minerals in the world.
Co-founder and President of numerous organizations, Dr. Arem has enjoyed a lifelong career in mineralogy and gemology. He has been a Smithsonian scientist and Curator, a consultant to many well-known companies and institutions, and a prolific author and speaker. Although his main activities have been as a gem cutter and dealer, his focus has always been education.
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