mineral

Agate with Quartz Druzy

Silicon Dioxide (SiO2) - Microcrystalline and Macrocrystalline varieties

Hardness: 6.5-7 on Mohs scale. Color: Waxy grey-blue chalcedony base with reddish-brown rinds and translucent crystalline druzy. Luster: Vitreous to waxy. Structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific Gravity: 2.6-2.65.

Hardness: 6
Luster: Vitreous to waxy

Identified March 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 through the deposition of silica from groundwater into cavities (vugs) within volcanic host rocks or limestone. The reddish-brown crust suggests a high iron oxide presence during the formation of the outer layers. These are typically millions of years old, often dating from the Cenozoic era.

Uses & applications

Commonly used for lapidary work (cabbing and polishing), jewelry, spiritual/metaphysical collecting, and as decorative display specimens.

Geological facts

Agate is a variety of chalcedony characterized by its fineness of grain and brightness of color. The internal cavity seen in this specimen is a 'vug' where quartz crystals had space to grow, creating the 'druzy' sparkle.

Field identification & locations

Identify in the field by checking for a translucent waxy texture and conchoidal fractures. Look for it in riverbeds or agricultural fields near volcanic regions. To collectors, the presence of internal crystal structures within a weathered rind is a key indicator.

Other mineral specimens

See all

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

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

Epidote

Epidote - Ca2(Al2,Fe3+)3(SiO4)3(OH)

mineral