Sedimentary Rock (Cryptocrystalline Quartz)

Red Jasper

Silicon Dioxide (SiO₂)

Hardness: 6.5-7 on Mohs scale. Color: Opaque red, often with brown, black, or grey veins/spots due to impurities. Luster: Dull to vitreous, waxy. Crystal Structure: Trigonal, microcrystalline. Cleavage: None. Specific Gravity: 2.58-2.91.

Hardness: 6
Luster: Dull to vitreous, waxy

Identified November 1, 2025More sedimentary rock (cryptocrystalline quartz) →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Red Jasper is a microcrystalline variety of quartz, formed from the precipitation of silica-rich solutions or as a primary constituent of sediments. Its red color is due to high iron oxide (hematite) content. It often forms in volcanic environments, hydrothermal vents, or as petrified wood. Geological age varies widely depending on the deposit, from billions of years old to relatively recent formations.

Uses & applications

Primarily used as an ornamental stone in jewelry (cabochons, beads, carvings), decorative objects, and sometimes as a facing stone in construction. It is also used in lapidary arts.

Geological facts

Jasper is one of the oldest known gemstones, used by ancient civilizations for tools, seals, and amulets. It is believed to have protective and grounding properties in various cultures. The name 'jasper' means 'spotted stone' and comes from the Old French 'jaspre', ultimately from the Greek 'iaspis'.

Field identification & locations

Red Jasper can be identified in the field by its distinct opaque red color, hardness (it will scratch glass), and its lack of cleavage. Its common presence as rounded pebbles or nodules can also be a clue. It is found worldwide, with notable deposits in India, Russia, Indonesia, Egypt, Australia, and the USA (Oregon, California, Idaho).

Other sedimentary rock (cryptocrystalline quartz) specimens

See all

Blue Chalcedony

Cryptocrystalline Quartz (SiO2)

mineral

Chert (Agatized/Chalcedony variety)

Microcrystalline Quartz (SiO2)

sedimentary

Carnelian and White Quartz Bracelet

Silicon Dioxide (SiO2) - specifically Carnelian (Chalcedony) and Rock Crystal/Snow Quartz

mineral

Chert / Flint

Cryptocrystalline quartz (SiO2)

Sedimentary

Druzy Chalcedony (Agate Geode)

Silica (SiO2) - Cryptocrystalline Quartz with druzy macrocrystalline quartz

mineral

Geode with Quartz and possibly Jasper/Hematite

Quartz (SiO2) and Chalcedony (cryptocrystalline SiO2), possibly stained by iron oxides

Mineral/Sedimentary Geode