gemstone
Tumbled amethyst
Amethyst, purple variety of quartz (SiO₂)
AI-generated identification · may be incorrectMohs hardness 7; translucent purple with a vitreous luster and trigonal crystal structure. This smooth, rounded piece has no visible cleavage; quartz has conchoidal fracture and specific gravity about 2.65.
Identified More gemstone →
Explore Tumbled amethyst in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Mohs hardness 7; translucent purple with a vitreous luster and trigonal crystal structure. This smooth, rounded piece has no visible cleavage; quartz has conchoidal fracture and specific gravity about 2.65.
Formation & geological history
Formed as quartz crystals in silica-rich fluids, commonly within gas cavities in volcanic rocks; amethyst deposits range from ancient to geologically recent. This specimen has been mechanically tumbled and polished.
Uses & applications
Used in jewelry, carvings, décor, and mineral collections.
Geological facts
Amethyst’s purple color is associated with trace iron and natural irradiation; heating can turn it yellow-orange, producing citrine-like material.
Field identification & locations
Recognize it by its purple color, glassy luster, and hardness; common sources include Brazil, Uruguay, and Zambia. A small tumbled stone like this typically sells for about $1–$10 USD.
More like this
Other gemstone specimens
Ammolite
Ammolite (Biogenic Aragonite with trace elements; fossils of Placenticeras meeki and Placenticeras intercalare)
mineral
Gemstone Ring
N/A - Set piece of jewelry, likely Amethyst or Garnet with Diamond or CZ
gemstone
Amber
Succinite (Organic Gemstone)
mineral
Diamond and Gold Jewelry
Carbon (Diamond) / Au (Gold)
gemstone
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
sedimentary
Pearl necklace
Pearl, primarily aragonite (CaCO₃) and conchiolin
gemstone