mineral

Translucent yellow-green chalcedony, possibly common opal

Microcrystalline quartz (SiO₂), potentially mixed with opaline silica (SiO₂·nH₂O)

AI-generated identification · may be incorrect

Waxy to vitreous luster, pale yellow-green color, translucent edges, and cloudy orbicular/veined internal texture; quartz hardness is about 7 Mohs, while opal is about 5.5–6.5. The strong blue glow is likely ultraviolet fluorescence from included minerals or a UV-reactive coating, not inherent blue coloration.

Identified August 19, 2026More mineral →

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At a glance

Common name: Translucent yellow-green chalcedony, possibly common opal
Scientific name: Microcrystalline quartz (SiO₂), potentially mixed with opaline silica (SiO₂·nH₂O)
Category: mineral
Identified: August 19, 2026
Method: Standard

AI Estimated Value

About $5–$30 for a common polished specimen; roughly $30–$100+ if naturally colored, strongly fluorescent, and attractively patterned.

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 and fractures, precipitating chalcedony or opal in volcanic rocks and sediments; ages range from recent to millions of years. Exact identification requires daylight inspection, UV wavelength testing, and hardness or specific-gravity tests.

Uses & applications

Used as a lapidary stone for cabochons, carvings, and decorative specimens; attractive translucent material may have modest gemstone appeal.

Geological facts

The visible pattern resembles orbicular chalcedony or “flower agate,” though the yellow-green coloration may reflect iron-bearing inclusions, dye, or treatment.

Field identification & locations

Common sources include Brazil, Madagascar, Mexico, Turkey, and the western United States. Check for conchoidal fracture, lack of cleavage, uniformity of color, and whether fluorescence persists after washing; avoid scratching until treatment is known.