mineral

Sunstone (Feldspar variety)

(Ca,Na)(Al,Si)4O8 with Hematite or Goethite inclusions

AI-generated identification · may be incorrect

Hardness: 6-6.5 on Mohs scale; Color: Orange, reddish-brown, or peach with metallic glitters; Luster: Vitreous to pearly; Crystal structure: Triclinic; Cleavage: Perfect in two directions.

Hardness: 6-6
Color: Orange, reddish-brown, or peach with metallic glitters
Luster: Vitreous to pearly

Identified July 2, 2026More mineral →

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Physical properties

Hardness: 6-6.5 on Mohs scale; Color: Orange, reddish-brown, or peach with metallic glitters; Luster: Vitreous to pearly; Crystal structure: Triclinic; Cleavage: Perfect in two directions.

Formation & geological history

Formed in igneous environments, particularly in basaltic lava flows or pegmatites. The metallic schiller effect is caused by tiny plate-like inclusions of hematite, copper, or goethite aligned with the mineral's structure.

Uses & applications

Primarily used as a gemstone for jewelry (rings, pendants, beads) and as a collector's specimen due to its unique optical properties.

Geological facts

The shimmering effect seen in sunstone is called 'aventurescence.' It was once used by Viking navigators for orientation at sea on cloudy days, leading to its nickname as a 'Viking Compass' or Sunstone.

Field identification & locations

Identify by looking for the metallic 'spangles' or shimmer when rotated under light. Commonly found in Oregon (USA), Norway, India, and Tanzania. It is the state gemstone of Oregon.