Rock Identifier
Dalmatian Jasper (Dyed Blue) (Peralkaline Rock with Arfvedsonite and Blue Dye) — igneous
igneous

Dalmatian Jasper (Dyed Blue)

Peralkaline Rock with Arfvedsonite and Blue Dye

Hardness: 5.5-7 (Mohs scale), Color: Dyed Blue with natural black spots, Luster: Vitreous to dull when unpolished, Crystal structure: Microcrystalline, Cleavage: None, Specific gravity: 2.6-2.7

Hardness
5
Identified More igneous

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Physical properties

Hardness: 5.5-7 (Mohs scale), Color: Dyed Blue with natural black spots, Luster: Vitreous to dull when unpolished, Crystal structure: Microcrystalline, Cleavage: None, Specific gravity: 2.6-2.7

Formation & geological history

Formed from peralkaline igneous activity where magma cools and crystallizes. The black spots are Arfvedsonite (amphibole), not Tourmaline as often misclaimed. Most specimens originate from Chihuahua, Mexico. These specific specimens have been artificially dyed blue.

Uses & applications

Primarily used for decorative purposes, lapidary carvings, tumbled stones, and costume jewelry. It is a popular stone in metaphysical circles and for beginner rock collections.

Geological facts

Despite its trade name 'Dalmatian Jasper', it is not actually a jasper (sedimentary) but an igneous rock. The blue color seen in this image is 100% artificial, as the natural stone is white to cream-colored.

Field identification & locations

Identify by the distinct 'Dalmatian' spotting pattern of black crystals against a lighter matrix. If found in blue as shown here, it is a clear indicator of dyeing. Natural stones are primarily found in Mexico.