mineral

Tumbled Aventurine and Smoky Quartz (Ametrine variant)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale); Luster: Vitreous; Colors: Green (Aventurine) and Purple/Yellow (Ametrine); Crystal Structure: Trigonal/Hexagonal; Cleavage: None (Conchoidal fracture).

Hardness: 7 (Mohs scale)
Luster: Vitreous

Identified July 10, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Luster: Vitreous; Colors: Green (Aventurine) and Purple/Yellow (Ametrine); Crystal Structure: Trigonal/Hexagonal; Cleavage: None (Conchoidal fracture).

Formation & geological history

Formed in hydrothermal veins or pegmatites where silica-rich fluids cool and crystallize. Green aventurine gets its color from fuchsite inclusions, while ametrine forms from iron impurities and temperature variations during crystal growth.

Uses & applications

Commonly used in tumbled stone jewelry, decorative carvings, metaphysical healing practices, and as collector specimens.

Geological facts

Aventurine is known for the phenomenon called aventurescence, a shimmering effect caused by inclusions. Ametrine is a rare natural combination of Amethyst and Citrine in the same crystal.

Field identification & locations

Identify by hardness (it will scratch glass), color distribution, and the presence of characteristic inclusions under magnification. Frequently found in Brazil, India, and Bolivia.