mineral

Likely chalcedony (gray agate), rough fragment

Microcrystalline quartz, SiO₂; “agate” applies if distinct banding is present

AI-generated identification · may be incorrect

Translucent to opaque gray-blue with a waxy to dull luster and irregular fracture; quartz hardness is 6.5–7, with no cleavage. The image does not show clear crystal faces or diagnostic banding, so identification is provisional.

Identified September 25, 2026More mineral →

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Physical properties

Formation & geological history

Chalcedony forms when silica-rich fluids fill cavities or fractures and precipitate microscopic quartz fibers, commonly in volcanic rocks; its age depends on the host deposit.

Uses & applications

Used for carvings, beads, cabochons, and decorative objects; ordinary rough pieces have little industrial or collector value.

Geological facts

Chalcedony is a broad term for microcrystalline quartz. A hardness test and a freshly cut or polished surface can help distinguish it from softer look-alikes.

Field identification & locations

The reported location is in the Krishna River region of Andhra Pradesh, where alluvial material may include silica-rich stones; the image alone cannot confirm local provenance. Look for hardness near 7, a glassy-to-waxy surface, and any fine bands when wet or polished.