Synthetic Glass (Man-made)

Goldstone (Red)

Aventurine Glass (Cupriferous glass)

Hardness: 5.5-6 (Mohs scale); Color: Reddish-brown with gold/copper speckles; Luster: Vitreous with aventurescence; Structure: Amorphous (glass); Cleavage: None (Conchoidal fracture); Specific Gravity: ~2.5

Hardness: 5
Color: Reddish-brown with gold/copper speckles
Luster: Vitreous with aventurescence

Identified March 17, 2026More synthetic glass (man-made) →

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Physical properties

Formation & geological history

Manufactured in a low-oxygen environment where copper salts are added to molten glass. As the glass cools slowly, the copper ions aggregate into tiny metallic crystals. This process was famously refined in 17th-century Venice.

Uses & applications

Used primarily in jewelry making, lapidary arts, decorative carvings, and as a popular 'healing stone' in metaphysical practices.

Geological facts

Legend claims Italian monks accidentally dropped copper filings into molten glass, creating 'Goldstone.' While it is not a natural mineral, it is one of the few man-made materials widely traded alongside precious gemstones.

Field identification & locations

Identify by its uniform, brilliant metallic glitter (aventurescence) and smooth, glassy texture. It is not found in nature; if found outdoors, it is likely a lost decorative piece or discarded tumble stone.

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