metamorphic
Nuummite
Orthoamphibole (mixture of Anthophyllite and Gedrite)
Hardness: 5.5-6.0; Color: Black with metallic iridescent flecks (blue, gold, silver); Luster: Vitreous to sub-metallic; Crystal structure: Orthorhombic; Cleavage: Perfect; Specific gravity: 2.85-3.57
- Hardness
- 5
- Color
- Black with metallic iridescent flecks (blue, gold, silver)
- Luster
- Vitreous to sub-metallic
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Physical properties
Hardness: 5.5-6.0; Color: Black with metallic iridescent flecks (blue, gold, silver); Luster: Vitreous to sub-metallic; Crystal structure: Orthorhombic; Cleavage: Perfect; Specific gravity: 2.85-3.57
Formation & geological history
Formed through high-grade metamorphism of volcanic rocks. It is one of the oldest rocks on Earth, dating back approximately 2.8 to 3 billion years to the Late Archean period.
Uses & applications
Primarily used for high-end lapidary work, jewelry, and as a collector's specimen. It is popular in metaphysical circles as a stone for protection and grounding.
Geological facts
Nuummite was discovered in 1982 near Nuuk, Greenland. Because of its extreme age and the harsh environment where it is found, it is considered a rare and exotic stone.
Field identification & locations
Identify by its 'labradorescence-like' metallic flashes against a deep black background. In the field, look for needle-like crystals in a dense, dark metamorphic matrix. Found almost exclusively in Greenland.
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