sedimentary

Jasper

Silicon dioxide (SiO2)

Hardness: 6.5-7 (Mohs); Color: Red, brown, dark pinkish hues; Luster: Vitreous to waxy; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; Fracture: Conchoidal.

Hardness: 6
Color: Red, brown, dark pinkish hues
Luster: Vitreous to waxy

Identified July 11, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs); Color: Red, brown, dark pinkish hues; Luster: Vitreous to waxy; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; Fracture: Conchoidal.

Formation & geological history

Formed through the accumulation of volcanic ash or silica-rich sediments. Over millions of years, silica-rich solutions precipitate and fill voids, eventually forming microcrystalline quartz. The coloration is typically due to iron inclusions.

Uses & applications

Used primarily in lapidary work for jewelry (cabochons), interior decoration, and as a collectible metaphysical or decorative stone.

Geological facts

Jasper is an opaque variety of chalcedony. Historically, it was known as the 'supreme nurturer' and has been used by ancient civilizations for amulets and cylinder seals for thousands of years.

Field identification & locations

Identify in the field by its hardness (will scratch glass), opaque nature, and smooth, waxy fracture surfaces. Commonly found in riverbeds or coastal areas with high volcanic or sedimentary activity.