saf-ahyuh r

Discovered 1819 in Greenland, this gemstone is usually found in massive forms in host rocks. Eudialyte is an extremely rare and complex mineral that occurs in red-violets, pinks, blues, yellows and browns. Well-formed crystals are rare, and opaque material is often fashioned in cabochons.

Eudialyte Polished
Eudialyte Classification
Common Name Eudialyte
Species Eudialyte
Eudialyte Optical Properties
Transparency Translucent - Opaque
Dispersion Strength: None
Refractive Index 1.591-1.633
Birefringence 0.003-0.01
Optic Character Uniaxial
Optic Sign Positive
Polariscope Reaction Aggregate (AGG), Doubly Refractive (DR)
Fluorescence SWUV: Inert
LWUV: Inert
Pleochroism Unobservable
Eudialyte Characteristic Physical Properties
Hardness 5-5.5
Streak White To Pale Pink
Specific Gravity 2.740-3.000
Toughness Poor
Luster Vitreous, Dull
Stability Poor
Fracture Uneven
Cleavage Perfect, in one direction, Poor, in one direction
Eudialyte Chemistry & Crystallography
Chemical Formula Na4(Ca,Ce)2(Fe,Mn,Y)ZrSi8O22(OH,Cl)2
Crystal System Trigonal
Chemistry Classification Silicate

Eudialyte Colors

  • Blue Eudialyte Blue
  • Pink Eudialyte Pink
  • Multi-color Eudialyte Multi-color
  • Red Eudialyte Red
  • Orange Eudialyte Orange
  • Yellow Eudialyte Yellow
  • Brown Eudialyte Brown
  • Purple Eudialyte Purple

Countries of Origin

Russian Federation (the)

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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.