gemstone

Green Jasper / Plasma

Microcrystalline Quartz (Chalcedony), SiO2 with inclusions

Hardness of 6.5 to 7 on the Mohs scale, predominantly green color with darker mottling or white quartz/chalcedony veins, waxy to vitreous luster, cryptocrystalline crystal structure, conchoidal fracture with no true cleavage, and a specific gravity of roughly 2.58 to 2.91.

Identified July 30, 2026More gemstone →

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Physical properties

Formation & geological history

Formed via the precipitation of silica-rich fluids in rock fractures, cavities, or sedimentary environments, often associated with hydrothermal activity or volcanic processes over geological timescales.

Uses & applications

Widely used for ornamental carvings, cabochons in jewelry, polished specimens, and lapidary art due to its attractive colors and durability.

Geological facts

Green jasper varieties like plasma have been prized since antiquity for seals, amulets, and ornamental objects, often noted for their toughness and fine polishing capabilities.

Field identification & locations

Found globally in alluvial gravels, riverbeds, and weathered rock outcrops where silica-bearing solutions have percolated. Identify by its high hardness, inability to be scratched by steel, waxy luster, and opaque green coloration.

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