mineral

Polished bloodstone (heliotrope), probable

Chalcedony (microcrystalline quartz, SiO₂) with iron-oxide inclusions

AI-generated identification · may be incorrect

Dark green to nearly black, glossy, opaque, and smoothly tumbled, with reddish-brown spots visible in the image. Hardness is about 6.5–7 Mohs; no visible cleavage; cryptocrystalline quartz structure; specific gravity about 2.6.

Identified August 31, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich groundwater fills cavities or fractures, with disseminated hematite or jasper producing the red inclusions. Common deposits are Phanerozoic volcanic and sedimentary terrains; exact age depends on locality.

Uses & applications

Used for cabochons, beads, carvings, and inexpensive jewelry, as well as ornamental objects and lapidary collections.

Geological facts

Bloodstone is traditionally associated with the “blood” of Christ and has been used as a seal stone since antiquity. The red inclusions are iron oxides, not actual blood.

Field identification & locations

Identify it by its waxy-to-glassy polish, very fine texture, dark green-black body, and contrasting red flecks; it should scratch ordinary glass but not quartz. Common sources include India, Brazil, Australia, China, and Madagascar.