sedimentary

Likely tumbled jasper or chert specimens

Microcrystalline quartz (SiO₂), commonly jasper/chert; exact identification is uncertain from the photograph

AI-generated identification · may be incorrect

Opaque brown to gray, earthy colors, dull to waxy luster, and no visible crystal faces; quartz hardness is about 6.5–7 Mohs, with conchoidal fracture and specific gravity near 2.6. The pieces appear naturally rounded or tumbled, and the lower gray specimen may contain iron oxides or other inclusions.

Identified August 11, 2026More sedimentary →

Explore Likely tumbled jasper or chert specimens in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

At a glance

Common name: Likely tumbled jasper or chert specimens
Scientific name: Microcrystalline quartz (SiO₂), commonly jasper/chert; exact identification is uncertain from the photograph
Category: sedimentary
Identified: August 11, 2026
Method: Standard

AI Estimated Value

About $2–$15 for common tumbled pieces; $20–$100+ for unusually patterned, large, or lapidary-grade specimens.

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 and chert form when silica-rich fluids replace or cement sediment, often during diagenesis; many examples range from Precambrian to Cenozoic in age. Their colors commonly result from iron, manganese, clay, or organic impurities.

Uses & applications

Used for cabochons, beads, carvings, tumbling, and ornamental objects; chert has also been used historically for sharp tools and fire-starting.

Geological facts

A steel file or quartz crystal should not easily scratch genuine jasper, while glass may be scratched by it. The brown pieces could also be weathered agate, petrified wood, or another iron-stained silica rock.

Field identification & locations

Common worldwide, especially in volcanic and sedimentary terrains; inspect for waxy luster, conchoidal fracture, and lack of cleavage. A close image, locality, streak, and hardness test would improve identification.