mineral

Tumbled yellow jasper or petrified wood fragment

Microcrystalline quartz (chalcedony), SiO₂, possibly iron-oxide-bearing jasper

AI-generated identification · may be incorrect

Opaque mustard-yellow, cream, and brown with a waxy-to-dull luster and polished rounded surface; hardness about 6.5–7 Mohs, no visible cleavage, cryptocrystalline structure, and specific gravity near 2.6. The small size and indistinct pattern make exact identification uncertain from the image alone.

Identified August 11, 2026More mineral →

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At a glance

Common name: Tumbled yellow jasper or petrified wood fragment
Scientific name: Microcrystalline quartz (chalcedony), SiO₂, possibly iron-oxide-bearing jasper
Category: mineral
Identified: August 11, 2026
Method: Standard

AI Estimated Value

$1–$10 for a small common tumbled piece; approximately $10–$40 if it has unusually attractive patterning or confirmed petrified-wood texture.

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

Jasper forms when silica-rich fluids replace or cement sediments, commonly incorporating iron oxides that produce yellow, orange, and brown colors; formation ages vary widely from Precambrian to recent. If the pattern is cellular or woody under magnification, it may instead be silicified petrified wood.

Uses & applications

Used as inexpensive lapidary material for cabochons, beads, tumbled stones, and small carvings; valued mainly for color and pattern rather than rarity.

Geological facts

Jasper is an opaque variety of chalcedony, unlike agate, which is typically translucent and banded. A glassy scratch test should not be attempted on the specimen; a steel point may be scratched by quartz-rich material.

Field identification & locations

Common in volcanic and sedimentary terrains worldwide, including the western United States, Madagascar, Brazil, and Australia. Look for an opaque body, quartz-like hardness, and iron-stained coloration; a loupe or cut surface can distinguish jasper from petrified wood.