HELIOTROPE, or BLOODSTONE, a cryptocrystalline variety of quartz, darlfgreen in colour, with small spots of red jasper, resembling drops of blood. The name, from the Greek 17/Xmos, sun, and Tp€iros, to turn, is stated by Pliny (Vat. Hist., xxxvii. 60) to be due to its giving, when thrown into water, a red reflexion of the light of the sun. The modern heliotrope, however, is Pliny's prasius (op. tit,, xxxvi. 34); and what he terms heliotrope was apparently a leek-green prase or plasma., abundantly veined with blood-red jasper. Heliotrope is found in the Isle of Runs, and in Mull of Cantyre, Argyllshire, and in several foreign localities. It is of common occurrence in the trap-rocks of the Deccan. Medicinal and other virtues were formerly ascribei to the stone. It is used for signet rings and a variety of ornamental articles.