sedimentary

Jasper (specifically variegated or swamp jasper beads)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Hardness: 6.5-7 (Mohs scale), Color: Earth tones including olive green, mustard yellow, and clay brown with swirling patterns, Luster: Vitreous to waxy, Crystal Structure: Trigonal (microcrystalline), Cleavage: None/Conchoidal fracture, Specific Gravity: 2.58-2.91

Hardness: 6

Identified March 18, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the deposition of silica-rich waters in sedimentary environments, specifically when volcanic ash or fine sediments are petrified. Often found in deposits dating from the Cretaceous to early Cenozoic eras.

Uses & applications

Primarily used for lapidary work, including prayer beads (Tasbih), cabochons for jewelry, and ornamental carvings due to its durability and high polish.

Geological facts

Jasper has been used in antiquity for seals and talismans; the name comes from the Greek word 'iaspis', meaning spotted stone. It is an opaque variety of chalcedony that can contain up to 20% foreign materials, which determines its color and pattern.

Field identification & locations

Identify in the field by its opacity (it will not let light pass through thick sections), hardness (it will scratch glass), and smooth conchoidal fracture. Commonly found in river beds or desert regions of India, Russia, and the USA.

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