mineral

Likely polished agate or chalcedony pebble

Chalcedony, microcrystalline quartz (SiO₂); exact variety cannot be confirmed from the image

AI-generated identification · may be incorrect

Smooth, pale gray-blue, waxy to vitreous luster with cloudy and possibly banded inclusions. Quartz hardness is 7 Mohs; microcrystals are too fine to see clearly, and the specimen appears tumbled or polished.

Identified September 24, 2026More mineral →

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Physical properties

Formation & geological history

Silica-rich fluids deposited quartz in cavities or fractures, later forming chalcedony; the pebble may have been naturally rounded or mechanically tumbled. Its geological age and source are not identifiable from the image.

Uses & applications

Used for beads, cabochons, ornaments, and collecting; chalcedony is also used for carvings and small decorative objects.

Geological facts

Chalcedony is a fine-grained form of quartz and can occur in many colors and patterns, including agate when distinctly banded.

Field identification & locations

Look for hardness, a smooth conchoidal fracture on an unpolished area, and any fine bands; the photo alone cannot distinguish agate from other chalcedony. Chalcedony occurs worldwide, commonly in volcanic rocks and sedimentary deposits.