mineral

Red agate (possibly dyed chalcedony)

Chalcedony, microcrystalline SiO₂; agate is banded chalcedony

AI-generated identification · may be incorrect

Translucent deep red with a polished, waxy-to-vitreous luster; quartz-family trigonal microcrystals, Mohs hardness 6.5–7, no obvious cleavage. The vivid, uniform color may indicate dye treatment; the photo alone cannot confirm identity or treatment.

Identified October 11, 2026More mineral →

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Physical properties

Formation & geological history

Chalcedony forms as silica precipitates in cavities and fractures, commonly in volcanic rocks; deposits range from ancient to geologically recent. Red agate may derive its color naturally from iron oxides or be artificially dyed.

Uses & applications

Used for beads, cabochons, and decorative objects; agate is also used in ornaments and some precision components.

Geological facts

Agate is a variety of chalcedony, not a separate mineral species; translucent color under backlighting is not diagnostic by itself.

Field identification & locations

Check for natural banding, a glassy fracture, and hardness near 7; dye may concentrate in cracks or pores. Agates occur worldwide, including Brazil, Uruguay, India, and the United States.