mineraloid (man-made glass)

Goldstone (Brown)

Aventurine Glass (Silicon Dioxide infused with Copper crystals)

Hardness: 5.5-6.0 Mohs; Color: Brownish-red with metallic gold specks; Luster: Vitreous; Crystal Structure: Amorphous (glass matrix) with isometric copper inclusions; Specific Gravity: ~2.5-2.8.

Hardness: 5
Color: Brownish-red with metallic gold specks
Luster: Vitreous

Identified June 14, 2026More mineraloid (man-made glass) →

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Physical properties

Hardness: 5.5-6.0 Mohs; Color: Brownish-red with metallic gold specks; Luster: Vitreous; Crystal Structure: Amorphous (glass matrix) with isometric copper inclusions; Specific Gravity: ~2.5-2.8.

Formation & geological history

Goldstone is a synthetic glass created in a low-oxygen reducing atmosphere. Molten glass is infused with copper salts which crystallize into tiny metallic platelets upon cooling. It originated in 17th-century Venice, Italy.

Uses & applications

Primarily used for jewelry, lapidary carvings, tumbled stones, and decorative ornaments. It is also popular in holistic and metaphysical communities.

Geological facts

Legend says it was discovered by accident by Italian monks who dropped copper shavings into molten glass. It is often mistaken for natural Aventurine or Sunstone but is strictly a man-made product.

Field identification & locations

Identify by the uniform distribution of highly reflective copper 'glitter' within the glass. Unlike natural stones, the sparkles are very geometric and evenly spaced. It is not found in nature; it is found in gem shops and craft stores.

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