Bloodstone, also known as heliotrope, is a variety of chalcedony, a microcrystalline form of quartz. This stone is recognized by its deep green body color, naturally speckled with contrasting red or reddish-brown inclusions. Because its appearance often resembles droplets of blood, this ancient gemstone has been used in jewelry and revered in various cultures for millennia.
Identifying Bloodstone: Composition and Formation
Bloodstone is a form of silica, specifically cryptocrystalline quartz known as chalcedony. Its characteristic dark green matrix is caused by minute mineral inclusions, such as chlorite or various amphibole group minerals. This base color provides a backdrop for the stone’s defining feature: vivid red spots.
These red markings are composed of iron oxide, most commonly hematite, deposited within the silica structure. The hematite inclusions range from bright specks to larger, splash-like patches, giving the stone its name. Bloodstone forms in the Earth’s crust through low-temperature processes, where silica-rich fluids permeate cracks and cavities in existing rock.
The geological setting is often within volcanic or sedimentary rocks, where silica is deposited in veins or nodules. As these fluids cool and solidify, the chalcedony forms, incorporating the iron oxides and green minerals. This process results in a durable stone, frequently found as pebbles in alluvial deposits after the softer host rock has eroded away.
Major Global Sources of Commercial Bloodstone
The majority of commercially available bloodstone is sourced from large-scale mining operations in a few global locations. India is the largest producer, yielding much of the high-quality material found today. Significant deposits are located on the Kathiawar Peninsula in the state of Gujarat.
Indian bloodstone is regarded for its deep forest green color and the sharp contrast provided by bright, well-defined red specks. Brazil is another major supplier, contributing substantial quantities of the gem, often extracted from vast geological formations. These large deposits support the global demand for bloodstone used in carvings, cabochons, and jewelry.
Australia also serves as an important source, particularly the state of Queensland. Madagascar supplies significant amounts of this chalcedony variety, making it a reliable producer alongside the primary nations.
Regional and Historical Localities
Beyond the major commercial hubs, bloodstone is found in numerous smaller, regionally significant, or historical locations. One historically significant European source is the Isle of Rum in Scotland, where it occurs in ancient lava flows. The deposit at Bloodstone Hill was quarried during the Stone Ages, where its flint-like properties made it valuable for crafting tools.
In North America, bloodstone is found across the western United States, though these deposits are smaller than international commercial sources. California has localities that yield the gemstone, along with finds in Oregon and Washington. These American finds often occur as stream-worn pebbles or small nodules in alluvial settings, accessible to local collectors.
Additional sources, often supplying material for domestic or regional use, include locations in Eastern Europe and China. These regional sources are important for their unique historical context and geological diversity.