sedimentary
Jasper with Quartz Veining
Silicon Dioxide (SiO2) - Cryptocrystalline Chalcedony
Hardness: 6.5-7 (Mohs scale), Color: Reddish-brown (iron inclusions) with white/translucent quartz, Luster: Dull to waxy, Crystal Structure: Hexagonal (microcrystalline), Cleavage: None (conchoidal fracture), Specific Gravity: 2.58-2.91
- Hardness
- 6
Identified More sedimentary →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6.5-7 (Mohs scale), Color: Reddish-brown (iron inclusions) with white/translucent quartz, Luster: Dull to waxy, Crystal Structure: Hexagonal (microcrystalline), Cleavage: None (conchoidal fracture), Specific Gravity: 2.58-2.91
Formation & geological history
Formed through the process of silica-rich fluids permeating volcanic ash or sedimentary beds (silicification). The white quartz veins indicate later stage hydrothermal activity where mineral-rich water filled fractures in the existing jasper. Can range from Precambrian to recent geological ages.
Uses & applications
Used primarily in lapidary work for cabochons, beads, and decorative carvings. Historically used for making tools due to its sharp conchoidal fracture. Also popular as a landscape stone or for mineral collectors.
Geological facts
Jasper is an opaque variety of chalcedony. The red color in this specimen is caused by iron(III) oxide (hematite) impurities. It has been used by humans for thousands of years, prominently featured in ancient cylinder seals and jewelry from Mesopotamia.
Field identification & locations
Identify in the field by its hardness (cannot be scratched by a steel knife), smooth waxy feel on breaks, and lack of transparency. Commonly found in riverbeds, deserts, or near volcanic deposits. Notable locations include the Western USA, Brazil, and India.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Shale or Slaty Mudstone
Argillaceous sedimentary rock
sedimentary
Chert Breccia
Brecciated Chert (Microcrystalline Silica)
sedimentary
Sandstone (Quartz-rich)
Arenite (SiO2)
sedimentary
Sandstone (with man-made markings)
Arenite (composed primarily of Quartz, SiO2)
sedimentary