Bloodstone
Chalcedony var. Bloodstone (Heliotrope) · Semi-Precious Gemstone / Collector Mineral
Crystal System
Trigonal (Hexagonal system); typically occurs in massive, microcrystalline, or cryptocrystalline habits.
Mineral Group
Silicates (Tectosilicate group); a variety of Chalcedony/Quartz.
Chemical Formula
SiO2 (Silicon Dioxide) with Fe2O3 (Hematite) inclusions
Formation Process
Hydrothermal; forms at low temperatures in cavities and fractures of volcanic rocks or as sedimentary deposits through silica-rich groundwater precipitation.
About This Crystal
A dark green, opaque cryptocrystalline quartz (chalcedony) featuring distinct red spots or streaks. It exhibits a waxy to vitreous luster and a smooth, tumbled surface texture.
Physical Characteristics
Color: Dark forest green with red inclusions; Streak: White; Cleavage: None; Fracture: Conchoidal; Specific Gravity: 2.58–2.64; Fluorescence: None to weak.
Optical Properties
Refractive Index: 1.530–1.543; Birefringence: up to 0.004; Pleochroism: None; Optical character: Aggregate (singly refractive/isotropic behavior).
Hardness & Durability
Origin Region
Primarily India; also found in Brazil, Australia, Germany, South Africa, and Scotland (Isle of Rum).
Hardness & Durability
Mohs Hardness: 6.5–7.0; Toughness: Very High (due to microcrystalline structure); Stability: Stable against light and most common chemicals.
Care & Maintenance
Safe to clean with warm soapy water and a soft brush. Avoid harsh chemicals like hydrofluoric acid. Ultrasonic cleaners are generally safe but use with caution if fractures are present.
Rarity & Value
Common; Value is driven by the distribution and intensity of the red 'blood' spots against a deep green ground. Usually very affordable.
Special Characteristics
Features characteristic red inclusions of iron oxide (Hematite) that resemble droplets of blood, often called the 'Heliotrope' effect.
Lore & History
Historically known as the 'Martyr's Stone' in Christian lore, specifically associated with the blood of Christ. In ancient Babylon and Egypt, it was used as an amulet to defeat enemies and increase physical strength.