mineral

Agate (Carnelian Agate)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Hardness: 6.5-7 on Mohs scale. Color: Translucent yellowish-orange to amber-brown. Luster: Waxy to vitreous. Crystal Structure: Hexagonal (trigonal microcrystalline). Cleavage: None, exhibits conchoidal fracture. Specific Gravity: ~2.58-2.64.

Hardness: 6
Color: Translucent yellowish-orange to amber-brown
Luster: Waxy to vitreous

Identified July 27, 2026More mineral →

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Physical properties

Formation & geological history

Forms primarily in volcanic gas cavities (vesicles) or sedimentary environments through precipitation of silica-rich water over millions of years, often colored by iron oxide impurities.

Uses & applications

Used extensively for lapidary arts, jewelry (cabochons, beads), decorative carvings, tumbling, and gemstone collecting. Historically used for signet rings and amulets.

Geological facts

Carnelian agate has been appreciated since antiquity; ancient Romans and Egyptians carved it into seals, beads, and protective talismans. Its warm translucent glow is enhanced when wet or backlit.

Field identification & locations

Identify by its smooth, waxy surface, translucent orange-amber tone, lack of cleavage, and durability (scratches glass). Common in river beds, beaches, and gravel deposits globally (e.g., Pacific Northwest, Brazil, India, Madagascar).

Other mineral specimens

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Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Soil with Mineral Detritus and Quartz Fragments

Regolith / Silicate Mineral Aggregate

sedimentary

Limonite / Goethite (Iron Ore Mineral nodule)

FeO(OH)·nH2O / FeO(OH)

mineral

Schist

Metamorphic

Septarian Pebble

Septarian nodule / Concretion

sedimentary

Potassium Feldspar (Orthoclase)

Orthoclase (KAlSi3O8)

mineral