man-made glass
Blue Goldstone
Synthetic glass with cobalt and copper inclusions
AI-generated identification · may be incorrectHardness: ~5.5 (Mohs scale), Color: dark blue/purple with sparkling metallic flecks, Luster: vitreous (glassy), Crystal structure: amorphous (glass) with crystalline inclusions, specific gravity: ~2.5
- Hardness
- ~5
Identified More man-made glass →
Explore Blue Goldstone in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: ~5.5 (Mohs scale), Color: dark blue/purple with sparkling metallic flecks, Luster: vitreous (glassy), Crystal structure: amorphous (glass) with crystalline inclusions, specific gravity: ~2.5
Formation & geological history
Man-made material. Originally created in Venice, Italy. Formed by melting silica, copper oxide, and other metal oxides (like cobalt or manganese for the blue color) in a reducing atmosphere.
Uses & applications
Used primarily in jewelry, cabochons, carvings, and as a decorative stone in collecting or crystal healing practices.
Geological facts
Despite its name, it contains no gold. The sparkles are typically tiny crystals of copper that precipitate out of the cooling glass. The blue version uses cobalt or manganese.
Field identification & locations
Identified by its deep color and distinct, dense, perfectly suspended metallic sparkles. It feels like glass and is often polished into smooth, tumbled shapes.
More like this
Other man-made glass specimens
Opalite
Synthetic glass / Opalized glass
gemstone
Likely tumbled red mineral or glass imitation
Indeterminate; possibilities include red jasper (microcrystalline quartz, SiO₂) or dyed chalcedony
mineral
Opalite
Synthetic glass / Opalized glass
gemstone
Green Obsidian Sphere (man-made glass)
Vitreous Silica with Chromium/Iron additives
mineralogical simulant
Sea Glass
Silicon dioxide (mostly)
mineral
Clear quartz crystal (likely)
Quartz, silicon dioxide (SiO₂)
mineral