mineral

Banded Agate (Agate Slice)

Silicon Dioxide (SiO2) - Variety of Chalcedony

Hardness: 6.5-7 on Mohs scale. Color: Multicolored concentric bands (white, tan, orange, grey). Luster: Waxy to vitreous. Crystal Structure: Hexagonal (cryptocrystalline). Cleavage: None (conchoidal fracture). Specific Gravity: 2.58-2.64.

Hardness: 6
Color: Multicolored concentric bands (white, tan, orange, grey)
Luster: Waxy to vitreous

Identified June 20, 2026More mineral →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed in cavities (vesicles) of volcanic rocks or ancient lavas, where silica-rich groundwater deposits layers of chalcedony over thousands of years. Often found in basaltic host rocks.

Uses & applications

Used extensively in jewelry (cabochons), interior decoration (coasters, bookends), precision pendulums, and as metaphysical healing stones.

Geological facts

The name Agate comes from the Achates River in Sicily. Each band represents a different pulse of mineral-rich water entering the rock cavity. Agates were used by ancient Sumerians for cylinder seals and ornaments as early as 3000 BCE.

Field identification & locations

Identify by its translucent nature when held to light and its distinct concentric banding patterns. Commonly found in Brazil, Uruguay, and the Lake Superior region of the USA. Look for waxy, nodular surfaces in volcanic outcrops.

Other mineral specimens

See all

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Schist

Metamorphic

Epidote

Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

metamorphic

Nephrite Jade

Nephrite

Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Green Apatite on Albite

Fluorapatite [Ca5(PO4)3F] on Albite [Na(AlSi3O8)]

mineral