The ancient thinking of the Indus Valley Civilization, placed the male and female principles as equals. The male principle, Shiva or D united with the female, Shakti or Ñ to form the Y hexagram or mandala. The hexagram was a symbol of the Sacred Marriage.
The earliest evidence of this symbol was found among coins from the excavation of the city of Ujjain in India. The coins have been dated to be 2000 - 3000 years old. These coins came into the possession of Colonel James Tod, the Political Agent to the Western Rajput States of India in the early 1800s.
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