igneous
Dalmatian Jasper
Peralkaline rock with Tourmaline spots
Hardness: 5.5-7 (Mohs); Color: Pale gray or cream with distinct black or dark brown spots; Luster: Vitreous to dull; Crystal structure: Microcrystalline; Cleavage: None
- Hardness
- 5
- Color
- Pale gray or cream with distinct black or dark brown spots
- Luster
- Vitreous to dull
Identified More igneous →
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Physical properties
Hardness: 5.5-7 (Mohs); Color: Pale gray or cream with distinct black or dark brown spots; Luster: Vitreous to dull; Crystal structure: Microcrystalline; Cleavage: None
Formation & geological history
Formed through the cooling of silica-rich magma that contains specific impurities of tourmaline (schorl) or arfvedsonite. It is primarily found in Chihuahua, Mexico.
Uses & applications
Used primarily in jewelry making for beads, cabochons, and decorative carvings; also popular in metaphysical collections and crystal healing.
Geological facts
Despite being called 'Jasper', it is technically an igneous rock (specifically an aplite or peralkaline rock) rather than a true chalcedony-based jasper. The black spots were long thought to be tourmaline, but recent studies suggest they are more likely arfvedsonite.
Field identification & locations
Identify by its unique spotted patterns resembling a Dalmatian dog breed. It is commonly found in desert regions of Mexico. Collectors should look for high contrast between the cream background and the dark spots.
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