sedimentary

Red Jasper

Microcrystalline quartz (SiO2) with Hematite (Fe2O3) impurities

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs); Color: Deep opaque red to reddish-brown; Luster: Vitreous to dull; Crystal Structure: Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific Gravity: 2.58-2.91

Hardness: 6
Color: Deep opaque red to reddish-brown
Luster: Vitreous to dull

Identified March 8, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed when silica-rich fluids permeate sedimentary or volcanic rocks, depositing microcrystalline quartz. Its red color is derived from iron inclusions (hematite). It can be found in volcanic deposits or as water-worn pebbles in riverbeds.

Uses & applications

Commonly used for lapidary work, cabochons for jewelry, decorative carvings, tumbled stones for collectors, and historically as seal stones or amulets.

Geological facts

In ancient times, Red Jasper was known as the 'stone of endurance' and was frequently used by warriors for protection. It is a variety of chalcedony that is uniquely opaque due to its high mineral impurity content.

Field identification & locations

Identify in the field by its intense red color, extreme hardness (it will scratch glass), and lack of transparency even when held to a strong light. Common locations include Brazil, India, USA (sway-valleys), and South Africa.