Chemical: SiO (a chalcedony family member of the quartz group)
Crystal System: None. Forms in massive formations
Formation: Associated with pegmatite dikes and certain igneous rocks
Unusual Properties: Heliotrope offers a very unusual combination of reds, greens, and yellows as shown above. It got its common name of bloodstone from what appears to be droplets of blood red colors, which in the Middle Ages was attributed to Christ’s blood shed on the earth. The stone is very long wearing and is cut en cabochon for men’s rings, and is used for ornamental carvings.