igneous
Dalmatian Jasper
Aplite with Arfvedsonite inclusions
Hardness: 5-7 Mohs; Color: Creamy white or pale grey with black spots; Luster: Dull to vitreous; Crystal Structure: Trigonal/Monoclinic; Specific Gravity: 2.58-2.91
- Hardness
- 5-7 Mohs
- Color
- Creamy white or pale grey with black spots
- Luster
- Dull to vitreous
Identified More igneous →
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Physical properties
Hardness: 5-7 Mohs; Color: Creamy white or pale grey with black spots; Luster: Dull to vitreous; Crystal Structure: Trigonal/Monoclinic; Specific Gravity: 2.58-2.91
Formation & geological history
Formed from igneous processes when cooling magma crystallizes. Despite the name 'Jasper', it is geologically an aplite, a fine-grained intrusive igneous rock. The black spots are minerals like Arfvedsonite or Tourmaline.
Uses & applications
Primarily used for decorative purposes, lapidary work, beads, tumbled stones, and metaphysical jewelry due to its unique pattern.
Geological facts
While marketed as a variety of Jasper (a sedimentary silica), it is actually an igneous rock. It is named for the Dalmatian dog breed due to its unique spotted appearance.
Field identification & locations
Identified by its distinctive black-on-tan spotted pattern resembling a dog's coat. It is predominantly found in Chihuahua, Mexico. Collectors should look for even distribution of spots and a smooth, even polish.
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