mineral

Dyed Agate (Tumbled)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Hardness: 6.5-7 on Mohs scale; Color: Artificially vibrant purple (natural agate is usually grey, brown, or white); Luster: Vitreous to waxy; Structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.60-2.65.

Hardness: 6
Luster: Vitreous to waxy

Identified March 23, 2026More mineral →

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Physical properties

Formation & geological history

Formed in volcanic rock cavities or ancient sedimentary rocks where silica-rich groundwater deposits layers over thousands of years. Natural agate dates back millions of years, though these specific specimens have undergone modern tumbling and chemical dyeing processes.

Uses & applications

Used primarily for decorative purposes, costume jewelry, healing crystals/spirituality markets, and as inexpensive souvenirs for collectors and children.

Geological facts

Agate is naturally porous, which allows it to absorb chemical dyes readily. This creates the neon and deep saturated colors (like this purple, and the blue/teal stones in the background) that do not occur in nature. Most dyed agates come from Brazil.

Field identification & locations

Identify in the field by its translucency and characteristic banding (though maskable by dye). To distinguish from natural purple stones like Amethyst, look for 'pooling' of color in cracks and a lack of natural crystal faces. Common in souvenir shops worldwide.

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