sedimentary

Jasper

Jasper (Silicon Dioxide, SiO2)

Hardness: 6.5-7 on Mohs scale. Color: Opaque pink to reddish-brown (caused by iron inclusions). Luster: Dull/waxy to vitreous. Crystal Structure: Hexagonal (Microcrystalline). Cleavage: None (conchoidal fracture). Specific Gravity: 2.58-2.91.

Hardness: 6
Color: Opaque pink to reddish-brown (caused by iron inclusions)
Luster: Dull/waxy to vitreous

Identified April 12, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the accumulation of silica in sedimentary environments, often near volcanic activity or in hydrothermal processes where silica-rich fluids permeate fine-grained sediments or volcanic ash. It belongs to the chalcedony family.

Uses & applications

Used primarily as a gemstone for jewelry (cabochons, beads), decorative carvings, and as a popular collected specimen for mineral enthusiasts due to its varied patterns.

Geological facts

The word 'Jasper' is derived from the Greek for 'spotted stone.' Pink varieties are often associated with the presence of hematite or manganese during the crystallization process. It was a favorite stone in antiquity across Babylonia and Egypt.

Field identification & locations

Identify in the field by its opaque nature (unlike translucent chalcedony), its high hardness (will scratch glass), and its characteristic smooth, shell-like (conchoidal) fracture surface. Found globally in riverbeds or mountain ranges.