mineral

Sunstone

Oligoclase (a plagioclase feldspar variant), (Na,Ca)(Al,Si)4O8

Hardness: 6-6.5 (Mohs scale); Color: Orange, reddish-brown, or yellow-gold; Luster: Vitreous to pearly; Crystal structure: Triclinic; Cleavage: Perfect in two directions; Features: Aventurescence (metallic glitter caused by hematite or copper inclusions).

Hardness: 6-6
Color: Orange, reddish-brown, or yellow-gold
Luster: Vitreous to pearly

Identified March 25, 2026More mineral →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed in cooling igneous rocks like pegmatites or basaltic lavas. The metallic glitter is caused by inclusions that crystallize under high temperatures during the cooling process. Common in Cenozoic deposits (approx. 15-30 million years old in some regions like Oregon).

Uses & applications

Primarily used as a gemstone for jewelry (rings, pendants, earrings), ornamental carvings, and by mineral collectors for its unique optical properties.

Geological facts

Also known as 'Heliolite.' Historically, some legends suggest Viking navigators used sunstones (or similar calcite 'Sunstones') as a polarizing filter to locate the sun on cloudy days. It became the official state gemstone of Oregon in 1987.

Field identification & locations

Identify in the field by its distinct orange-hued metallic 'schiller' or glitter when rotated under light. Commonly found in Oregon (USA), Norway, Tanzania, and India. Collectors should look for depth of color and clarity of metallic inclusions.

Other mineral specimens

See all

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Epidote

Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

metamorphic

Nephrite Jade

Nephrite

Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Green Apatite on Albite

Fluorapatite [Ca5(PO4)3F] on Albite [Na(AlSi3O8)]

mineral

Epidote

Epidote - Ca2(Al2,Fe3+)3(SiO4)3(OH)

mineral