mineral

Agate (or Chalcedony with Moss/Jasper Inclusions)

Silicon Dioxide (SiO2)

Hardness: 6.5-7 (Mohs scale); Color: Brown, tan, and translucent blue-gray; Luster: Vitreous to waxy; Crystal structure: Trigonal/Microcrystalline; Cleavage: None (Conchoidal fracture); Specific gravity: 2.58-2.64

Hardness: 6
Color: Brown, tan, and translucent blue-gray
Luster: Vitreous to waxy

Identified June 28, 2026More mineral →

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Physical properties

Formation & geological history

Formed as a primary mineral in cavities of volcanic rocks or as veins. This specimen likely formed through silica-rich groundwater filling voids in igneous host rock, creating the translucent chalcedony bands visible across the brown jasper-like matrix.

Uses & applications

Used primarily for jewelry (cabochons), lapidary art, and rock collecting. Also used in precision scales and mortars due to its hardness.

Geological facts

Agates are named after the Achates River in Sicily where they were first found. The 'bands' or translucent veins in this specimen are characteristic of the chalcedony family of minerals.

Field identification & locations

Identify by its waxy luster when wet, translucency against light, and high hardness (it will scratch glass). Commonly found in riverbeds, lake shores, and volcanic regions like the Pacific Northwest or Lake Superior region.

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sedimentary

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Mineral

Nephrite Jade

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Mineral/Rock

Banded Gneiss (River Rock/Pebble)

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