sedimentary

Red Moss Agate (Jasper)

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Hardness: 6.5-7 (Mohs scale); Color: Red, brownish-red, with white or translucent moss-like inclusions; Luster: Vitreous to waxy (when polished); Crystal structure: Trigonal (Cryptocrystalline); Cleavage: None (Conchoidal fracture); Specific gravity: 2.58-2.64

Hardness: 6
Luster: Vitreous to waxy (when polished)

Identified April 29, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the deposition of silica-rich groundwater in the cavities and veins of volcanic or sedimentary rocks, with the red color provided by iron oxide (Hematite) impurities. Often found in areas of past volcanic activity.

Uses & applications

Primarily used for ornamental objects, decorative towers (points), lapidary work, jewelry, and as a popular specimen for crystal healing and mineral collectors.

Geological facts

Despite the name 'Moss Agate', the inclusions are mineral-based (iron or manganese) and not organic or biological. Red variants are often referred to as Red Moss Jasper due to their higher opacity.

Field identification & locations

Identify by its hardness (it will scratch glass), its distinctive moss-like patterns, and its red hues. Found globally with significant deposits in India, Brazil, and the USA. Collectors look for high contrast between the red matrix and white/clear quartz.

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