mineral (man-made glass)

Goldstone

Aventurine glass

Hardness: 5.5-6.0 Mohs; Color: reddish-brown with gold-colored flecks; Luster: Vitreous; Crystal structure: Amorphous (glass) containing crystalline inclusions of copper; Cleavage: Conchoidal fracture.

Hardness: 5
Color: reddish-brown with gold-colored flecks
Luster: Vitreous

Identified May 25, 2026More mineral (man-made glass) →

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Physical properties

Formation & geological history

Goldstone is a synthetic, man-made glass produced in a low-oxygen reducing atmosphere. It was originally invented in 17th-century Venice by the Miotti family. Tiny crystals of metallic copper are formed within the glass during cooling.

Uses & applications

Primarily used as a semi-precious stone for jewelry, beads, figurines, and various ornamental carvings. It is popular in metaphysical circles as a 'stone of ambition'.

Geological facts

Legend says goldstone was discovered by accident by Italian monks spilling copper filings into molten glass, though the Miotti family held the original patent. It is not a natural mineral despite its name.

Field identification & locations

Identify by its intense, uniform sparkle (aventurescence) and smooth glass texture. It is not found in nature; any field discovery would be a discarded artifact or jewelry piece. Common colors include brown, blue, and green.