mineral

Amethyst (Hematoid Quartz)

Silicon Dioxide (SiO2) with Ferric Iron inclusions

Hardness: 7 (Mohs scale); Color: Purple with reddish-brown coating; Luster: Vitreous to earthy; Crystal Structure: Hexagonal (Trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Purple with reddish-brown coating
Luster: Vitreous to earthy

Identified June 20, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Purple with reddish-brown coating; Luster: Vitreous to earthy; Crystal Structure: Hexagonal (Trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or geodes within igneous rocks. This specimen shows amethyst crystallized with heavy iron oxide (hematite/goethite) inclusions or coating, often found in ancient volcanic environments.

Uses & applications

Used primarily in lapidary work, jewelry, and by mineral collectors for its unique double-colored appearance.

Geological facts

Amethyst gets its purple color from irradiation and iron impurities; the reddish 'skin' or inclusions on this specimen are known as hematoid quartz, creating a 'Red Amethyst' effect.

Field identification & locations

Identify by its distinct purple interior and hexagonal crystal points often covered in a rusty hematite crust. Commonly found in Thunder Bay, Canada, or Brazil. Collectors look for the contrast between the druzy purple and red oxidation.

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