sedimentary

Jasper (Green variety)

Silicon Dioxide (SiO₂)

Hardness: 6.5–7 on Mohs scale; Color: Deep forest green with occasional brownish or tan streaks; Luster: Dull/Waxy; Crystal Structure: Microcrystalline; Specific Gravity: 2.58–2.91; Cleavage: None (conchoidal fracture).

Hardness: 6
Color: Deep forest green with occasional brownish or tan streaks
Luster: Dull/Waxy

Identified March 16, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the accumulation of fine silica sediment and volcanic ash in sedimentary environments or hydrothermal veins. Often found in Precambrian formations upwards to more recent deposits through the process of silicification.

Uses & applications

Commonly used in lapidary work for cabochons, beads, and decorative ornaments. Also used historically for talismans and seal stones due to its durability and potential for high polish.

Geological facts

Green jasper was exceptionally popular in the ancient world, particularly during the Minoan and Hellenistic periods. It is often referred to as 'Plasma' when the green color is consistent and translucent, though this specimen appears more opaque and matte.

Field identification & locations

Identify by its extreme hardness (cannot be scratched by a steel knife) and waxy, smooth texture when rubbed. Commonly found in riverbeds, desert pavements, and coastal regions globally. Collectors look for unique banding or patterns.