The OTO (Ordo Templi Orientis) was founded in 1895, and became famous through Aleister Crowley's association. This is a genuine occult sex majick medallion.
Aleister Crowley OTO Occult Sex Majick Medallion
The medallion is solid 10k gold, and weighs 17 g. It is 1 1/4 inches diameter, and is stamped on the back "10k" down bottom, and "OTO" up top. The front has an "Ouroborous" (world serpent eating his own tail) with a ruby for an eye; which sybolizes the eternal life/rebirth cycle. Inside the serpent is a "Phi" in white gold; which is the ancient symbol for knowledge. (the Greeks held Phi, the 21st letter of their alphabet, to be sacred, the root of knowledge; used as the root in philosoPHI, theosoPHI etc.) The numeric representation of Phi is 1.618, and is known as the Golden Ratio or the Divine Ratio. This ratio is considered a sacred number, and was used by the great initiates into the esoteric mystery schools; including Davinci, Aristotle, Galileo, Newton, Crowley, and many others not in the public eye. A little light was shed on the subject in Dan Brown's novel "The Davinci Code". Together, these symbols on this OTO medallion represented HIDDEN ETERNAL KNOWLEDGE to Crowley and his followers; and was used in many of their secret rites and ceremonies, and to identify each other.