mineral

Yellow chalcedony (likely lemon agate or yellow jasper)

Microcrystalline quartz, SiO₂; possibly iron-bearing jasper or chrysoprase-like chalcedony

AI-generated identification · may be incorrect

Polished/tumbled, translucent to opaque yellow with a waxy-to-glassy luster and no visible cleavage; quartz hardness is about Mohs 6.5–7, with specific gravity near 2.6. The rounded shape and polish indicate a processed geological specimen.

Identified September 16, 2026More mineral →

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At a glance

Common name: Yellow chalcedony (likely lemon agate or yellow jasper)
Scientific name: Microcrystalline quartz, SiO₂; possibly iron-bearing jasper or chrysoprase-like chalcedony
Category: mineral
Identified: September 16, 2026
Method: Standard

AI Estimated Value

About $3–$20 for a common tumbled piece; $20–$100+ for larger, vivid, natural, or attractive lapidary-quality 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

Forms when silica-rich groundwater fills cavities or fractures, depositing cryptocrystalline quartz; yellow coloration commonly comes from iron hydroxides or other impurities. Deposits occur in volcanic and sedimentary terrains, generally from relatively young to ancient silica-forming systems.

Uses & applications

Used for cabochons, beads, carvings, décor, and inexpensive lapidary specimens; durable enough for jewelry but less valuable than fine transparent gemstones.

Geological facts

Chalcedony is quartz made of microscopic intergrowths of quartz varieties. A stronger identification would require translucency, hardness, and possibly a streak or specific-gravity test.

Field identification & locations

Commonly found in Brazil, Madagascar, India, Mexico, Uruguay, and the western United States. Identify by its smooth waxy appearance, lack of cleavage, hardness, and resistance to scratching by steel; avoid confusing it with dyed glass or resin.