sedimentary

Red Jasper

Jasper (Silica-rich Microcrystalline Quartz, SiO2 with Iron Oxide)

Hardness: 6.5–7 (Mohs scale), Color: Mahogany red to brick red, Luster: Dull/Waxy to Vitreous (when polished), Crystal Structure: Trigonal (microcrystalline), Cleavage: None (conchoidal fracture), Specific Gravity: 2.58–2.91

Hardness: 6

Identified March 21, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the deposition of silica-rich sediments in volcanic or sedimentary environments. The red color is caused by the inclusion of hematite (iron oxide). It can be found in formations ranging from the Precambrian to recent geologic ages.

Uses & applications

Used primarily in lapidary work for jewelry (cabochons, beads), decorative objects, and as an ornamental stone in landscaping and aquariums.

Geological facts

Jasper has been used as a gemstone for thousands of years; it was a favorite in the ancient world, mentioned in the Bible and used by the Minoans for seals. Some specimens like this one feature 'veining' where quartz or calcite has filled cracks in the stone.

Field identification & locations

Identify in the field by its deep red color, high hardness (cannot be scratched by a steel knife), and smooth, conchoidal fracture patterns. Commonly found in riverbeds, glacial deposits, and pebble beaches globally.

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