mineral

Blue-green slag glass or chalcedony-like material

Likely industrial glassy slag; exact identification requires testing

AI-generated identification · may be incorrect

Translucent blue-green, vitreous luster, irregular conchoidal fracture, and no visible crystal faces. Apparent hardness is roughly 5–6, but hardness and specific gravity cannot be confirmed from the image.

Identified September 21, 2026More mineral →

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Physical properties

Formation & geological history

The smooth, melted appearance and unusual color suggest human-produced furnace slag or glass rather than a natural mineral; if natural, possible alternatives include chalcedony or chrysoprase. Geological age is indeterminate.

Uses & applications

Slag and glassy fragments are mainly collected as curiosities or used decoratively; chalcedony varieties may be used in cabochons and carvings.

Geological facts

The brown outer rind and internal swirled/translucent zones are common in weathered slag. A magnet, streak, and scratch test can help distinguish slag from natural silica minerals.

Field identification & locations

Inspect for bubbles, flow lines, metallic inclusions, and a sharp glassy fracture—these favor slag. Natural chalcedony is typically more uniformly waxy and silica-rich; common locations include industrial fill, beaches, and historic smelting sites.