mineral
Goldstone
Avventurina (Man-made Glass with Copper inclusions)
AI-generated identification · may be incorrectHardness: 5.5-6. Color: Reddish-brown with metallic speckles. Luster: Vitreous with aventurescence. Crystal Structure: Amorphous (glass matrix) containing cubic copper crystals. Cleavage: None. Specific Gravity: 2.5-2.8.
- Hardness
- 5
- Color
- Reddish-brown with metallic speckles
- Luster
- Vitreous with aventurescence
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Physical properties
Hardness: 5.5-6. Color: Reddish-brown with metallic speckles. Luster: Vitreous with aventurescence. Crystal Structure: Amorphous (glass matrix) containing cubic copper crystals. Cleavage: None. Specific Gravity: 2.5-2.8.
Formation & geological history
Goldstone is a synthetic material created in a low-oxygen reducing atmosphere. Molten glass is mixed with copper salts; as it cools slowly, copper ions precipitate into tiny, highly reflective metallic crystals. Originally perfected in 17th-century Venice.
Uses & applications
Used extensively in jewelry making (beads, cabochons), carvings, decorative ornaments, and metaphysical collecting.
Geological facts
Despite its name, goldstone contains no gold; the 'gold' appearance comes from copper. Legend says it was discovered by accident when Italian monks spilled copper filings into molten glass, though the process likely predates that story.
Field identification & locations
Identified by its uniform glittery appearance and glass-like feel. In the field, look for a smooth, non-porous surface that sparkles intensely under direct light. It is often confused with natural Sunstone but has much more uniform glitter.
