mineral

Tumbled green gemstone, likely dyed howlite or serpentine

Most consistent with dyed howlite (Ca2B5SiO9(OH)5); exact identification requires testing

AI-generated identification · may be incorrect

Opaque blue-green with dark gray-black veining and a polished vitreous-to-waxy luster; likely Mohs 3–6 depending on material. Massive, non-crystalline appearance; no visible cleavage.

Identified August 11, 2026More mineral →

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At a glance

Common name: Tumbled green gemstone, likely dyed howlite or serpentine
Scientific name: Most consistent with dyed howlite (Ca2B5SiO9(OH)5); exact identification requires testing
Category: mineral
Identified: August 11, 2026
Method: Standard

AI Estimated Value

Typically $2–$15 for a small polished/tumbled piece; substantially more only if laboratory-confirmed as a rare natural gemstone.

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

Opaque blue-green with dark gray-black veining and a polished vitreous-to-waxy luster; likely Mohs 3–6 depending on material. Massive, non-crystalline appearance; no visible cleavage.

Formation & geological history

Howlite forms as a borate mineral in evaporite-associated deposits, commonly in arid regions; serpentine forms by hydration of ultramafic rocks. The vivid color and strong veining may result from human dyeing, so geological age cannot be determined from the image.

Uses & applications

Used as an inexpensive tumbled bead, cabochon, or ornamental stone; not suitable for durable fine jewelry if it is howlite because it scratches relatively easily.

Geological facts

Dyed howlite is often marketed as “turquoise,” though it is not turquoise. Similar green material may be serpentine, dyed magnesite, or imitation turquoise.

Field identification & locations

Check hardness, streak, and magnification: howlite is relatively soft and commonly shows fine gray webbing; turquoise is usually harder and has a blue-green waxy appearance. Common sources include California and Nova Scotia for howlite, and global ultramafic belts for serpentine.