saf-ahyuh r

Ranging from green to brownish black in color, gadolinite is a mineral that counts Russia as one of its primary sources. Interestingly, gadolinite is prized for the two rare earth elements it contains: yttrium and cerium.

Gadolinite Polished
Gadolinite Classification
Common Name Gadolinite
Species Gadolinite
Gadolinite Optical Properties
Transparency Transparent - Opaque
Dispersion Strength: Strong Fire
Refractive Index Over The Limit 1.770-1.820
Birefringence 0.010- 0.050
Optic Character Biaxial
Optic Sign Positive
Polariscope Reaction Doubly Refractive (DR)
Pleochroism None
Gadolinite Characteristic Physical Properties
Hardness 6.5-7
Streak White And Greenish Gray
Specific Gravity 4.000-4.650
Toughness Poor
Luster Vitreous, Resinous, Greasy
Fracture Conchoidal, Splintery
Cleavage None
Gadolinite Chemistry & Crystallography
Chemical Formula Y2Fe2+Be2(Si2O10) or (Ce,La, Nd,Y)2Fe2+Be2(Si2O10)
Crystal System Monoclinic
Chemistry Classification Silicate

Gadolinite Colors

  • Brown Gadolinite Brown
  • Black Gadolinite Black
  • Green Gadolinite Green

Alternate Names


Countries of Origin

Angola; Czechia; Madagascar; Kazakhstan; Portugal; Austria; Mongolia; Sweden; Mozambique; Pakistan; Korea (the Republic of); Malawi; China; Russian Federation (the); Brazil; Poland; France; United Kingdom of Great Britain and Northern Ireland (the); Argentina; United States of America (the); Hungary; Sri Lanka; Japan; Switzerland; India; Spain; Canada; Norway; Namibia; Finland; Denmark; Italy; South Africa; Australia; Germany; Tajikistan


Care must be taken with Gadolinite because the material is soluble in acid and is radioactive.

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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.