man-made glass

Blue Goldstone

Synthetic glass with copper or cobalt/manganese inclusions

AI-generated identification · may be incorrect

Hardness: 5-5.5 (Mohs), Color: Dark blue with silvery or bluish sparkles, Luster: Vitreous (glassy), Crystal structure: Amorphous base with crystalline metallic flecks, Cleavage: None (conchoidal fracture).

Hardness: 5-5

Identified July 24, 2026More man-made glass →

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Physical properties

Formation & geological history

Manufactured in a laboratory or factory setting. Created by melting silica glass with metal oxides (like cobalt or manganese) and allowing it to crystallize under specific cooling conditions.

Uses & applications

Used primarily in lapidary arts, jewelry making, and as a decorative collector's item or carving material.

Geological facts

Goldstone was originally invented in 17th century Venice. While reddish-brown goldstone uses copper, blue goldstone uses cobalt or manganese to achieve its dark night-sky appearance.

Field identification & locations

Easily identified by its intense sparkle against a dark, homogeneous glassy background and conchoidal fracture. Often sold alongside natural stones in metaphysical and gem shops.