man-made glass mineral simulant

Goldstone

Aventurine Glass (SiO2 + Cu small inclusions)

AI-generated identification · may be incorrect

Hardness: 5.5-6 on Mohs scale; Color: Reddish-brown with metallic copper flecks; Luster: Vitreous to metallic; Structure: Amorphous (glass); Cleavage: None/Conchoidal fracture; Specific gravity: 2.5-2.8

Hardness: 5
Color: Reddish-brown with metallic copper flecks
Luster: Vitreous to metallic

Identified June 6, 2026More man-made glass mineral simulant →

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Physical properties

Formation & geological history

Goldstone is a synthetic glass created in a low-oxygen reducing atmosphere. It was originally invented in 17th-century Venice by the Miotti family. Molten glass is infused with copper oxide, which crystallizes into tiny metallic triangular and hexagonal crystals as it cools slowly.

Uses & applications

Primarily used for jewelry (cabochons, beads), decorative carvings, tumbelstones, and metaphysical collecting.

Geological facts

Legend claims it was discovered by accident when Italian monks spilled copper filings into molten glass, but the process actually predates this story. It is often mistaken for the natural mineral Sunstone.

Field identification & locations

Identify by its uniform distributed copper 'glitter' and smooth glass texture. It is not found in nature; it is exclusively mass-produced in factory settings world-wide.