sedimentary
Red Jasper
Opaque microcrystalline quartz (SiO2) with iron inclusions
Hardness: 6.5-7 Mohs; Color: Brick red to brownish-red with occasional bands; Luster: Dull to waxy; Crystal Structure: Hexagonal (trigonal); Fracture: Conchoidal; Specific Gravity: 2.58-2.91
- Hardness
- 6
- Color
- Brick red to brownish-red with occasional bands
- Luster
- Dull to waxy
Identified More sedimentary →
Explore Red Jasper in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6.5-7 Mohs; Color: Brick red to brownish-red with occasional bands; Luster: Dull to waxy; Crystal Structure: Hexagonal (trigonal); Fracture: Conchoidal; Specific Gravity: 2.58-2.91
Formation & geological history
Forms when fine-grained silica-rich sediments or volcanic ash are lithified. Its red color is derived from iron (hematite) inclusions that diffused through the silica during formation. Most common in ancient Precambrian or Phanerozoic deposits.
Uses & applications
Used extensively as a gemstone for jewelry (cabochons, beads), decorative carvings, lapidary art, and occasionally for metaphysical purposes.
Geological facts
Jasper is often found in massive form rather than distinct crystals. Because of its hardness, it was used in ancient times to create drills and scrapers. The name is derived from the Greek 'iaspis', meaning 'spotted stone'.
Field identification & locations
Identify by its deep red color, opacity (it will not let light through even at the edges), and smooth, waxy surface when worn by water. Found globally in areas with high silica and iron content, such as stream beds and coastal regions.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Cone-in-cone structure (Limestone)
Cone-in-cone structure (Secondary Sedimentary Structure)
sedimentary
Sandstone Grain
Clastic Sedimentary Rock Grain (SiO2 dominated)
sedimentary
Chert Breccia
Brecciated Chert (Microcrystalline Silica)
sedimentary
Shale or Slaty Mudstone
Argillaceous sedimentary rock
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary