metamorphic

Tumbled greenstone or serpentine pebble

Serpentinite, chiefly serpentine-group minerals (Mg₃Si₂O₅(OH)₄); possibly nephrite jade if notably tough and dense

AI-generated identification · may be incorrect

Smooth, rounded, pale yellow-green surface with dull to waxy luster and faint veining; likely Mohs 3–6, with no visible crystals or cleavage. Exact identification requires hardness, density, and translucency tests.

Identified August 26, 2026More metamorphic →

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At a glance

Common name: Tumbled greenstone or serpentine pebble
Scientific name: Serpentinite, chiefly serpentine-group minerals (Mg₃Si₂O₅(OH)₄); possibly nephrite jade if notably tough and dense
Category: metamorphic
Identified: August 26, 2026
Method: Standard

AI Estimated Value

About $1–$10 as a common tumbled pebble; $20–$200+ if verified as attractive, high-quality nephrite jade.

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

Serpentinite forms when ultramafic mantle rocks undergo hydration during metamorphism, commonly in ophiolites and subduction zones; the specimen is likely naturally water-worn or tumbled. Its precise geological age cannot be determined from the image.

Uses & applications

Commonly used as decorative stone, carvings, beads, and landscaping material; higher-quality nephrite jade is used in jewelry and sculpture.

Geological facts

Serpentine and jade can look similar, but jade is substantially tougher and generally denser. Avoid acid or destructive tests; a steel scratch test and specific-gravity measurement are more useful.

Field identification & locations

Common in California, New Zealand, Italy, Canada, Russia, and ultramafic terrains worldwide; identify by green color, waxy feel, veining, and relatively low hardness. The photograph alone cannot distinguish serpentine from low-grade jade or another greenstone.