mineral

Agate Geode

Microcrystalline Quartz (SiO2)

Mohs hardness: 6.5-7; Color: translucent white to gray with visible banding; Luster: waxy to vitreous; Crystal structure: hexagonal/trigonal; Cleavage: none.

Hardness: 6
Color: translucent white to gray with visible banding
Luster: waxy to vitreous

Identified May 9, 2026More mineral →

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Physical properties

Mohs hardness: 6.5-7; Color: translucent white to gray with visible banding; Luster: waxy to vitreous; Crystal structure: hexagonal/trigonal; Cleavage: none.

Formation & geological history

Formed primarily in volcanic rock cavities or ancient hydrothermal environments where silica-rich fluids deposited layers over time. This specimen shows a druzy quartz center surrounded by banded chalcedony.

Uses & applications

Commonly used for ornamental carvings, jewelry, decorative home decor, and as metaphysical or collectible display pieces.

Geological facts

Agates are often found as nodules within volcanic rocks. The banding seen in the star shape is formed through successive layers of silica deposition. This piece has been machine-cut and polished into a star shape.

Field identification & locations

Identify by characteristic banding and waxy texture. Natural specimens typically have a rough outer husk. Found globally in Brazil, Uruguay, and the United States.