mineral

Tumbled jasper or chalcedony pebble

Microcrystalline quartz (SiO₂), likely iron-stained jasper/chalcedony

AI-generated identification · may be incorrect

Small rounded, polished-looking pebble with reddish-brown and gray-white zones, waxy to vitreous luster, and no visible cleavage. Quartz hardness is about 7 Mohs; specific gravity is approximately 2.6.

Identified August 16, 2026More mineral →

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Physical properties

Formation & geological history

Formed when silica-rich groundwater fills cavities or fractures, later incorporating iron oxides that create the red-brown coloration; commonly derived from volcanic or sedimentary rocks. Exact geological age cannot be determined from the image.

Uses & applications

Used as a decorative stone, lapidary material, cabochon, or inexpensive gemstone; not generally used for construction at this size.

Geological facts

The specimen may be jasper if it is opaque and dense, or chalcedony if partly translucent; the image suggests a mixture or iron-stained chalcedony. Surface rounding may be natural stream wear or tumbling.

Field identification & locations

Identify with a glass-scratch test, performed cautiously: quartz should scratch ordinary glass. Look for a waxy surface, conchoidal fracture, and red iron-oxide bands; common sources include volcanic terrains, stream gravels, and silica-rich deposits worldwide.