Bloodstone

Bloodstone earns its name honestly: it is a dark green chalcedony scattered with small, bright red spots of iron oxide (usually hematite or jasper inclusions) that look, at a glance, like droplets of blood against a green field. The older name for the same stone, heliotrope, comes from an ancient belief that the material could turn the sun’s reflection blood-red when submerged in water — more poetry than mineralogy, but the name stuck alongside “bloodstone” and both are still used interchangeably in the trade today.

Species and variety. Bloodstone is a variety of chalcedony, the cryptocrystalline (fine-grained, fibrous) form of quartz, and its opacity and formation alongside true jaspers mean it is sometimes classed as a jasper variety rather than a chalcedony one — the boundary between the two trade terms is genuinely blurry, and both descriptions appear in reputable sources. Either way, the underlying material is silicon dioxide, SiO2, the same chemistry as agate, carnelian, and onyx.

Appearance and color range. The base color is a deep, somewhat opaque green, ranging from dark forest green to nearly black, with the defining red or reddish-brown spots distributed unevenly through the stone. Stones with well-distributed, vivid red spotting against clean green are the most sought after; a muddy or faint spot pattern is worth less regardless of overall size.

Hardness and everyday care. At roughly 6.5–7 on the Mohs scale, bloodstone holds up well to daily wear in rings and bracelets, resisting scratches from ordinary contact. Like other chalcedony varieties it is not especially tough against sharp impacts, so it is best stored separately from harder gems and cleaned with mild soap and water rather than harsh chemicals or ultrasonic cleaning.

Where it is found. India has historically been a major source, with additional production from Brazil, Australia, the United States, and China.

Birthstone role. Bloodstone appears in the historical (pre-20th-century) monthly lists for both March (alongside jasper) and December (alongside ruby) — an unusual case of one stone anchoring two different months in the same older system, a pattern that modern lists dropped in favor of one or two stones per month. None of the three modern systems (US 1912, UK 2013, US current) retain bloodstone in either month; today it survives as a birthstone claim only through that older tradition, not current jewelry-trade practice.