mineral

Crackle Agate / Dyed Agate

Agate (Silicon dioxide / SiO2)

Hardness: 6.5-7 (Mohs scale), Color: In this case, artificially dyed blue with a crackle pattern, Luster: Vitreous, Crystal structure: Cryptocrystalline, Cleavage: None, Specific gravity: 2.58-2.64

Hardness: 6

Identified June 18, 2026More mineral →

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Physical properties

Hardness: 6.5-7 (Mohs scale), Color: In this case, artificially dyed blue with a crackle pattern, Luster: Vitreous, Crystal structure: Cryptocrystalline, Cleavage: None, Specific gravity: 2.58-2.64

Formation & geological history

Agates form primarily in volcanic rocks or ancient lavas, in cavities produced by volatiles. The crackle effect seen here is artificially induced by heating the stone and rapidly cooling it to create surface fractures, followed by dying to introduce color into the cracks.

Uses & applications

Predominantly used in inexpensive jewelry, craft making, and as decorative pieces.

Geological facts

This specific piece has been heavily treated. While natural agate is a prized semi-precious stone, 'crackle' agates are almost always heat-treated and dyed to achieve this highly unnatural but aesthetically pleasing look.

Field identification & locations

Identify by its characteristic crackled appearance which looks like broken glass, coupled with vibrant, often unnatural dye colors concentrated in the fractures. Natural agates generally display concentric banding.

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