mineral
Amethyst
Silicon dioxide (SiO2) with iron impurities
Hardness: 7 on Mohs scale; Color: Pale lavender to deep violet; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65
- Hardness
- 7 on Mohs scale
- Color
- Pale lavender to deep violet
- Luster
- Vitreous (glassy)
Identified More mineral →
Explore Amethyst in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 7 on Mohs scale; Color: Pale lavender to deep violet; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65
Formation & geological history
Forms in hydrothermal veins or as linings in geodes. The purple color is caused by irradiation of iron impurities within the quartz crystal lattice. Found in volcanic rocks.
Uses & applications
Primarily used as a gemstone in jewelry, as decorative specimens for collectors, and in alternative healing practices (crystal therapy).
Geological facts
Until the 18th century, amethyst was included in the cardinal gemstones alongside diamond, ruby, sapphire, and emerald. Large deposits found in Brazil lowered its market value.
Field identification & locations
Identify by its characteristic purple color and quartz-like fracture. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Look for hexagonal crystal points or purple mass within rock cavities.
More like this
Other mineral specimens
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Sandstone with Mineral Veining or Crust
Sedimentary Sandstone (mostly SiO2 with Fe2O3 tinting)
sedimentary
Schist
Schist
Metamorphic
Potassium Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
mineral
Gypsum (variety Selenite or Alabaster)
Calcium sulfate dihydrate (CaSO4·2H2O)
Mineral
Nephrite Jade
Nephrite
Mineral/Rock