mineral

Quartz Crystal (Amethyst)

Silicon Dioxide (SiO2)

Hardness: 7 Mohs; Color: Pale violet to colorless; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Hardness: 7 Mohs
Color: Pale violet to colorless
Luster: Vitreous (glassy)

Identified May 23, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: Pale violet to colorless; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Formation & geological history

Formed in igneous or metamorphic environments when silica-rich hydrothermal fluids crystallize within cavities or veins. This specific piece appears to be a small crystal point with traces of iron impurities providing a faint purple hue.

Uses & applications

Used in electronics (oscillators), manufacturing glass, abrasives, jewelry (as a gemstone), and as a popular specimen for mineral collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. If it has a purple tint, it is chemically classified as Amethyst due to irradiation of iron impurities within the crystal structure.

Field identification & locations

Identify in the field by its hardness (it can scratch glass) and lack of cleavage. Found worldwide, frequently in river beds or within geodes in volcanic rock.