mineral

Tumbled chalcedony or quartz pebble

Microcrystalline quartz, SiO₂ (likely chalcedony); exact identification is uncertain from the image

AI-generated identification · may be incorrect

Rounded, polished, translucent pale olive-gray material with a waxy to vitreous luster and cloudy internal texture. Quartz has Mohs hardness 7, no cleavage, conchoidal fracture, and specific gravity about 2.65.

Identified September 22, 2026More mineral →

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At a glance

Common name: Tumbled chalcedony or quartz pebble
Scientific name: Microcrystalline quartz, SiO₂ (likely chalcedony); exact identification is uncertain from the image
Category: mineral
Identified: September 22, 2026
Method: Standard

AI Estimated Value

About $2–$15 as a common tumbled pebble; $20–$75 if unusually translucent, patterned, or suitable for quality lapidary work.

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

Likely formed when silica-rich groundwater filled cavities or fractures, later weathered and naturally or artificially rounded; its geological age cannot be determined visually. The yellow-green tint may reflect iron-bearing inclusions or surface staining.

Uses & applications

Used as a lapidary, carving, and decorative stone; attractive pieces may be made into cabochons or jewelry. Common tumbled specimens have modest commercial value.

Geological facts

Chalcedony is quartz composed of extremely fine intergrowths of quartz varieties, commonly displaying translucency and a waxy surface. The specimen could also be a low-grade jasper or quartzite, which require testing for distinction.

Field identification & locations

Common in volcanic cavities, sedimentary nodules, river gravels, and silica-rich veins worldwide; test hardness against steel or glass, inspect for conchoidal fracture, and use a 10× loupe for fibrous chalcedony texture.