mineral

Amethyst in Matrix

Silicon Dioxide with Iron Impurities (SiO2)

Hardness: 7 (Mohs scale), Color: Purple to violet crystals within a gray/brown host rock, Luster: Vitreous (glassy) for crystals and dull for the matrix, Crystal Structure: Hexagonal (trigonal), Specific Gravity: 2.65

Identified June 14, 2026More mineral →

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Physical properties

Formation & geological history

Formed in volcanic rocks (geodes or veins) when silica-rich fluids permeate cavities. The purple color is the result of irradiation and iron impurities. This specimen shows amethyst crystals still attached to their host 'matrix' rock.

Uses & applications

Used primarily for semi-precious jewelry, ornamental carvings, and as a popular specimen for mineral collectors and metaphysical practitioners.

Geological facts

Amethyst was once considered one of the 'Cardinal Gems' along with diamond, ruby, sapphire, and emerald until large deposits were found in Brazil in the 19th century.

Field identification & locations

Look for the characteristic purple color and hexagonal crystal terminations. It is commonly found in Brazil, Uruguay, and across North America. To identify in the field, check for hardness (cannot be scratched by steel) and lack of cleavage.

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