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Aeschynite is a rare earth mineral that is a rarely cut into a gemstone. Not only is it fairly rare it also contains elements like thorium and yttrium. Both elements are radioactive and some specimens and gemstones can be highly so. It is not recomended to store this mineral in inhabbited areas or to have prolonged exposure to the body.

Aeschynite Classification
Common Name Aeschynite
Species Aeschynite
Aeschynite Optical Properties
Transparency Semitransparent - Opaque
Dispersion Strength: Strong Fire
Refractive Index Over The Limit 2.190-2.500
Birefringence 0.150- 0.220
Optic Character Biaxial
Optic Sign Positive
Polariscope Reaction Aggregate (AGG), Doubly Refractive (DR)
Fluorescence SWUV: Inert
LWUV: Inert
Pleochroism None
Aeschynite Characteristic Physical Properties
Hardness 5-6
Streak Reddish Yellow
Specific Gravity 4.850-5.190 Typical:4.950
Toughness Poor
Luster Vitreous, Resinous
Fracture Conchoidal
Cleavage Poor
Aeschynite Chemistry & Crystallography
Chemical Name yttrium calcium iron titanium niobium hydroxide
Chemical Formula (Y, Ca, Fe, Th) (Ti, Nb)2 (O, OH)6
Crystal System Orthorhombic
Chemistry Classification Oxide

Aeschynite Colors

  • Yellow Aeschynite Yellow
  • Brown Aeschynite Brown
  • Black Aeschynite Black

Alternate Names

Aeschinite, Blomstrandine, Blomstrandinite, Eschynite, Priorite,Syn., Priorite,Taiyite

Countries of Origin


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Tim Matthews


Tim Matthews

Tim Matthews is President and Chief Executive Officer of Jewelry Television® (JTV), as well as a member of the company's Board of Directors. He oversees and leads all aspects of the company's powerful omni-digital retail platform that uniquely specializes in fine jewelry and gemstones. His passion for business and gemstones has led him to become a recognized expert in the field of gemology. He is a life member of the Gemmological Association of Great Britain (Gem-A) and has earned Gem-A's highest degrees, the Gemmology (FGA) and Diamond (DGA) diplomas. He is also a Graduate Gemologist (GG) of the Gemological Institute of America (GIA) and has also completed GIA's Graduate Diplomas in Diamonds, Colored Stones and Pearls. Under his leadership, JTV has become the leader in the sourcing and selling of color gemstones and jewelry.

This page was created on June 27, 2014.

This page was last edited on October 24, 2019.