mineral

Blue-green glassy mineral specimen, possibly chalcedony or slag glass

Uncertain; candidate minerals include chrysocolla-bearing chalcedony or copper-bearing glassy slag

AI-generated identification · may be incorrect

Dark blue-green, translucent to opaque, with a vitreous luster and irregular conchoidal-looking fractures; apparent hardness roughly 5–7 Mohs, but cannot be measured from the image. No clear crystal faces or cleavage are visible.

Identified September 1, 2026More mineral →

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At a glance

Common name: Blue-green glassy mineral specimen, possibly chalcedony or slag glass
Scientific name: Uncertain; candidate minerals include chrysocolla-bearing chalcedony or copper-bearing glassy slag
Category: mineral
Identified: September 1, 2026
Method: Standard

AI Estimated Value

$1–$10 as an unidentified fragment; approximately $10–$50 if confirmed attractive natural chalcedony, with higher values only for exceptional polished material.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Natural chalcedony forms when silica-rich fluids fill cavities and fractures, commonly in volcanic rocks; blue-green coloration may come from copper minerals. Industrial slag glass can look similar and forms during metal smelting, so origin and age are indeterminate.

Uses & applications

If natural chalcedony, it is used for cabochons, carvings, and collecting; copper minerals may be ornamental. Slag has little commercial value beyond study or decorative collecting.

Geological facts

The rounded, glassy fragment and vivid blue-green color are not diagnostic; bubbles, flow textures, or metallic inclusions would favor slag, while waxy texture and silica hardness would favor chalcedony.

Field identification & locations

Test streak, hardness, and specific gravity; chalcedony should resist a steel knife and leave a white streak, whereas glassy slag may scratch more readily and show bubbles. Common possibilities occur near volcanic districts and historic smelters.