sedimentary

Red Jasper Concretion

Cryptocrystalline Quartz (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs), Color: Brick red to brownish-red, Luster: Vitreous to dull, Crystal Structure: Trigonal/Microcrystalline, Specific Gravity: 2.6-2.9, Cleavage: None

Hardness: 6

Identified May 27, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs), Color: Brick red to brownish-red, Luster: Vitreous to dull, Crystal Structure: Trigonal/Microcrystalline, Specific Gravity: 2.6-2.9, Cleavage: None

Formation & geological history

Formed through the accumulation of silica in sedimentary environments where iron oxides (hematite) provide the red pigmentation. It often forms through the cooling of silica-rich fluids or the replacement of organic material over millions of years.

Uses & applications

Used extensively in lapidary work for beads, cabochons, and decorative carvings; also a popular stone for jewelry and meditation practices.

Geological facts

Red jasper is known for its intense red color caused by iron inclusions. While often sold as a mineral, it is actually a variety of chalcedony, which is a microcrystalline form of quartz.

Field identification & locations

Identify in the field by its opaque nature, smooth conchoidal fracture, and inability to be scratched by a steel knife. It is commonly found in riverbeds and desert environments where volcanic or sedimentary activity has occurred.