sedimentary

Red Jasper (or Ironstone/Jasper Conglomerate)

Microcrystalline Quartz with Hematite inclusions (SiO2 + Fe2O3)

Hardness: 6.5-7 on Mohs scale; Color: reddish-brown, brick red, orange-brown; Luster: vitreous to earthy when wet; Crystal structure: trigonal (microcrystalline); Cleavage: none, shell-like (conchoidal) to uneven fracture; Specific gravity: 2.58-2.91.

Hardness: 6
Color: reddish-brown, brick red, orange-brown
Luster: vitreous to earthy when wet

Identified July 25, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the accumulation and cementation of microcrystalline quartz and iron oxide particles in marine or fluvial sedimentary environments, often associated with banded iron formations or weathered volcanic rocks.

Uses & applications

Used in lapidary arts for making cabochons, beads, decorative carvings, and as a popular landscape or collector beach stone.

Geological facts

Red jasper gets its rich reddish-brown coloration from fine iron oxide inclusions, primarily hematite. It has been used for thousands of years in seals, amulets, and decorative items across ancient civilizations.

Field identification & locations

Found on gravel beaches, riverbeds, and weathered outcrops worldwide. Identified by its distinct reddish-brown color, fine-grained sand-like texture, high hardness (scratches steel), and dense weight.

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