Heliotrope (Bloodstone)

Physical Properties

Hardness: 6.5-7 on Mohs scale. Color: Deep dark green with inclusions of iron oxide (hematite or jasper) appearing as red or brown spots. Luster: Vitreous to waxy. Crystal structure: Cryptocrystalline (Trigonal). Cleavage: None. Specific gravity: 2.58-2.64.

Formation & Geological History

Formed through the deposition of silica in rock cavities or fractures at low temperatures. It is a variety of chalcedony. The red spots are typically caused by inclusions of iron oxides or red jasper during the cooling and crystallization process.

Uses & Applications

Primarily used as a gemstone in jewelry (cabochons, rings), for carving seals or talismans, and as a popular specimen for mineral collectors.

Geological Facts

In the Middle Ages, the red spots were believed to be drops of Christ's blood, giving it the name 'Bloodstone'. It has been used for over two thousand years as a medicinal and protective amulet. It is the original March birthstone.

Field Identification & Locations

Identify by its characteristic forest-green body and red/brown speckles. It is commonly found in India, Brazil, Australia, and the United States. In the field, look for a smooth, waxy texture and verify its hardness against steel.

Identified on: 5/11/2026

Mode: Standard