mineral

Rough agate (chalcedony)

Microcrystalline quartz, SiO₂; likely translucent orange-brown chalcedony, possibly iron-stained

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; waxy to vitreous luster, translucent with orange, brown, gray, and white areas. Trigonal quartz structure at the microscopic level; no obvious cleavage, with conchoidal fracture. Distinct banding is not clearly visible in the photo.

Identified October 10, 2026More mineral →

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Physical properties

Formation & geological history

Silica-rich fluids deposited microscopic quartz in cavities or fractures, with iron compounds possibly causing the warm colors. Agate forms in many volcanic and sedimentary settings over geological time; the specimen’s age and locality cannot be determined from the image.

Uses & applications

Commonly cut and polished for jewelry, ornaments, and lapidary work; lower-grade material is collected or used decoratively.

Geological facts

Agate is a variety of chalcedony, not a separate mineral species. Its characteristic bands may be subtle or absent in small fragments.

Field identification & locations

The translucent, waxy appearance and irregular conchoidal fracture are consistent with chalcedony; hardness and a fresh fracture can help distinguish it from softer lookalikes. Agates occur worldwide, especially in volcanic rocks and alluvial deposits.