metamorphic

Tumbled dark green stone, likely serpentine or greenstone

Serpentinite (serpentine-group minerals), possibly chlorite- or amphibole-rich greenstone

AI-generated identification · may be incorrect

Mohs hardness typically 2.5–4; dark olive-green to brown, mottled, and waxy to dull after polishing, with no visible crystal faces or cleavage. Exact identification is uncertain from the photograph; a streak, hardness, and specific-gravity test would help.

Identified September 5, 2026More metamorphic →

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At a glance

Common name: Tumbled dark green stone, likely serpentine or greenstone
Scientific name: Serpentinite (serpentine-group minerals), possibly chlorite- or amphibole-rich greenstone
Category: metamorphic
Identified: September 5, 2026
Method: Standard

AI Estimated Value

About $2–$15 for a common tumbled stone; $20–$75 if unusually attractive, large, or confirmed as quality jade-like serpentine.

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 are hydrated during tectonic alteration, commonly in ophiolites and subduction zones; alteration ages vary widely. Greenstone may instead represent metamorphosed basalt.

Uses & applications

Used as a decorative carving and tumbled-stone material, ornamental tile, and occasionally jewelry; softer pieces are mainly collectible or lapidary specimens.

Geological facts

The rounded shape and uniform surface indicate tumbling or natural abrasion. Serpentine can resemble jade, but it is generally softer and less dense; fibrous varieties may contain chrysotile asbestos and should not be cut or drilled without testing.

Field identification & locations

Look for olive mottling, waxy luster, low hardness, and a pale green streak; common sources include California, Italy, New Zealand, Canada, and ophiolite belts worldwide. Confirm with gemological testing before calling it jade.