Nuummite

Big Photo

Nuuk, Sermersooq, Greenland
3.14 carats
© Brian Kosnar - Mineral Classics

Nuummite is named from the Municipality of Nuuk, where the stone was discovered in 1982.

Nuummite is an unapproved name for a metamorphic rock that combines two amphiboles - Anthophyllite and Gedrite. A striking iridescence is caused by the interference of light between these crystals.

Nuummite is an attractive ornamental rock. The material is cut and polished into cabochons. The stones exhibit red, green and blue flashes of colour against a dark brown to black background.

Nuummite Gemstones by Colour

This table shows the variety of hues this gemstone can be found in. Click on a photo for more information.
 

Nuummite Gemstones by Size

This table shows distribution of Nuummite gemstone sizes that are listed on this site. This can give a good indication as to the general availability of this gemstone in different sizes.
Contributed photos
Lightest:3.14 cts
Heaviest:4.53 cts
Average:3.89 cts
Total photos:3
Do you have a larger Nuummite? Why not upload a photo?
3.14ct to 3.28ct3.28ct to 3.42ct3.42ct to 3.56ct3.56ct to 3.70ct3.70ct to 3.84ct3.84ct to 3.97ct3.97ct to 4.11ct4.11ct to 4.25ct4.25ct to 4.39ct4.39ct to 4.53ct
General Information
Other Names/Trade Names:
Physical Properties of Nuummite
Mohs Hardness5.5 to 6
Walter Schumann, Gemstones of the world (2001)
More from other references
Specific Gravity3.18 to 3.37
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
Cleavage QualityPerfect
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
Optical Properties of Nuummite
Refractive Index1.635 to 1.663
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
Optical CharacterBiaxial/-
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
Birefringence0.022
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
Colour
Colour (General)Dark gray, brownish-black. Blue, golden yellow and reddish iridescence
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
More from other references
TransparencyOpaque
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
More from other references
Crystallography of Nuummite
Crystal SystemOrthorhombic
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
Further Information
Mineral information:Nuummite information at mindat.org
Significant Gem Localities
Greenland
 
  • Sermersooq
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