mineral

Blue Agate (likely dyed)

Silicon Dioxide (SiO2)

Hardness: 6.5–7 on Mohs scale; Color: Deep blue with concentric banding; Luster: Vitreous to waxy; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.60–2.65

Hardness: 6
Color: Deep blue with concentric banding
Luster: Vitreous to waxy

Identified April 2, 2026More mineral →

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Physical properties

Hardness: 6.5–7 on Mohs scale; Color: Deep blue with concentric banding; Luster: Vitreous to waxy; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.60–2.65

Formation & geological history

Formed as nodules in volcanic rocks or ancient lavas, where silica-rich groundwater fills cavities and precipitates over time. Intense blue agates like this are often natural chalcedony that has been artificially dyed to enhance color.

Uses & applications

Predominantly used for lapidary work, jewelry (cabochons, beads), decorative ornaments, and crystal healing collections.

Geological facts

Agate is a variety of chalcedony. Natural deep blue agate is extremely rare; most commercial 'blue agate' is produced by soaking gray agate in a solution of iron salts or chemicals then heating it.

Field identification & locations

Identify by its waxy luster, translucency, and distinct circular banding patterns. Often found in Brazil, India, and Germany. Collectors look for sharp, high-contrast bands.