Heliotrope (mineral)

The mineral aggregate heliotrope (from Greek ἥλιος, hḗlios “Sun”, τρέπειν, trépein “to turn”), also known as bloodstone, is a cryptocrystalline mixture of quartz that occurs mostly as jasper (opaque) or sometimes as chalcedony (translucent). The "classic" bloodstone is opaque green jasper with red inclusions of hematite.

Heliotrope
A heliotrope, also known as a bloodstone.
General
CategoryMineral
Formula
(repeating unit)		SiO2 (silicon dioxide)
Crystal systemTrigonal
Identification
ColorGreen with red or yellow spots
Mohs scale hardness6.5–7
LusterVitreous
Specific gravity2.61
Refractive index1.53–1.54
Birefringence0.004

The red inclusions are supposed to resemble spots of blood, hence the name bloodstone. The name heliotrope derives from various ancient notions about the manner in which the mineral reflects light. These are described, e.g., by Pliny the Elder (Nat. Hist. 37.165).[1]

Legends and superstitions

Heliotrope was called "stone of Babylon" by Albertus Magnus[2] and he referred to several magical properties, which were attributed to it from Late Antiquity. Pliny the Elder (1st century) mentioned first that the magicians used it as a stone of invisibility.[3] Damigeron (4th century)[4] wrote about its property to make rain, solar eclipse and its special virtue in divination and preserving health and youth. A Christian tradition states that the red spots come from blood falling upon the stone during the crucifixion of Jesus, as he was stabbed in the side by a Roman soldier.[5] Ancient Roman soldiers believed that the stone had the ability to slow bleeding and wore it for this reason.[6] In India holds that one can staunch the bleeding by placing upon wounds and injuries after dipping it in cold water, which may have a scientific basis in the fact that iron oxide, contained in the stone, is an effective astringent.[7] The Gnostics wore the stone as an amulet for longevity, for wealth and courage, to strengthen the stomach, and to dispel melancholy.[8] In the Middle Ages it was considered useful for animal husbandry.[9] The ancient Greeks and Romans wore the stone to bring renown and favor, to bring endurance, and as a charm against the bite of venomous creatures. Greek and Roman athletes favored it as talisman for success in their games. [10]

Sources

The primary source of the stone is Indonesia, especially in Purbalingga district. It is also found in Armenia, Azerbaijan, Brazil, Bulgaria, China, Australia, and the United States. There is also an outcrop of bloodstone on the Isle of Rum, in Scotland.

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References
  1. "heliotrope". Merriam-Webster Dictionary. m-w.com.
  2. Albertus Magnus, De Mineralibus, II.5. in: id., Opera omnia, ed. Borgnet (Paris, 1890), vol. 5, Mineralia: pp. 1–116; on p. 36. Cf. Peter J. Barta, The Seal-ring of Proportion and the magic rings (2016), p. 50f.
  3. Pliny, Naturalis Historia, xxxvii, 57. His account was copied verbatim by Isidore of Seville(c. 560-636), Etymologies, XVI,7,12. Cf. Peter J. Barta, The Seal-ring of Proportion and the magic rings (2016), p. 47.
  4. Damigeron, De lapidibus (Abel), ch. II, p. 165, lines 1-19; Damigeron (Pitra), ch. XIX, vol. iii, p. 325-326. Cf. Peter J. Barta, The Seal-ring of Proportion and the magic rings (2016), pp. 48-49.
  5. The Book of Talismans, Amulets and Zodiacal Gems, by William Thomas and Kate Pavitt, [1922] p.138
  6. The Book of Talismans, Amulets and Zodiacal Gems, by William Thomas and Kate Pavitt, [1922], p.138
  7. The Book of Talismans, Amulets and Zodiacal Gems, by William Thomas and Kate Pavitt, [1922] p.138
  8. The Book of Talismans, Amulets and Zodiacal Gems, by William Thomas and Kate Pavitt, [1922] p.139
  9. The Book of Talismans, Amulets and Zodiacal Gems, by William Thomas and Kate Pavitt, [1922] p.139
  10. The Book of Talismans, Amulets and Zodiacal Gems, by William Thomas and Kate Pavitt, [1922] p.139
  • Hall, Candy A. (1994). Gem Stones. DK Publishing. ISBN 1-56458-498-4.
  • Media related to Heliotrop at Wikimedia Commons
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