mineral
Polished banded agate
Agate, a variety of microcrystalline quartz (SiO₂)
AI-generated identification · may be incorrectMohs hardness 6.5–7; smooth, waxy to vitreous luster, with gray, cream, and brown bands. Microcrystalline quartz; no visible cleavage, typically conchoidal fracture. The image shows a polished oval specimen about 4 cm long.
Identified More mineral →
Explore Polished banded agate in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Mohs hardness 6.5–7; smooth, waxy to vitreous luster, with gray, cream, and brown bands. Microcrystalline quartz; no visible cleavage, typically conchoidal fracture. The image shows a polished oval specimen about 4 cm long.
Formation & geological history
Silica-rich fluids deposited successive layers in cavities, commonly in volcanic rocks; agate forms in many geological ages and settings.
Uses & applications
Used for cabochons, jewelry, ornaments, and collecting; agate is also used for precision components and small objects.
Geological facts
Its contrasting bands record changes in silica deposition and impurities as the cavity gradually filled.
Field identification & locations
Identify by its fine, curved or parallel color bands and hardness; common sources include Brazil, Uruguay, India, and the United States. This appears to be a polished agate cabochon or palm stone.
More like this
Other mineral specimens
Gneiss or Schist
Gneiss or Mica Schist with Garnet
Metamorphic
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Tumbled granite
Granite, a coarse-grained felsic intrusive igneous rock
igneous
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Pegmatite with Tourmaline and Quartz
Igneous Pegmatite
igneous
Granite
Granite (Phaneritic intrusive igneous rock)
igneous