man-made glass / industrial byproduct

Cullet Glass / Slag Glass

Amorphous silica glass

AI-generated identification · may be incorrect

Hardness 5.5-6 on Mohs scale, vitreous luster, conchoidal fracture, transparent to translucent, vibrant blue color.

Identified July 18, 2026More man-made glass / industrial byproduct →

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Physical properties

Hardness 5.5-6 on Mohs scale, vitreous luster, conchoidal fracture, transparent to translucent, vibrant blue color.

Formation & geological history

Man-made material, typically a byproduct of glass manufacturing or decorative chunks produced for landscaping and decoration.

Uses & applications

Used in landscaping, aquariums, decorative arts, and sometimes sold as a faux gemstone or "obsidian" to unsuspecting buyers.

Geological facts

Often mistaken for natural blue obsidian, which is extremely rare in nature. The bright, uniform color and complete lack of crystal structure confirm its artificial origin.

Field identification & locations

Identified by its conchoidal fracture, high transparency, lack of true crystal structure, and often the presence of spherical air bubbles. Common in landscaping supplies.