One version of the heterosexual symbol (i.e. a Mars symbol and Venus symbol horizontally or diagonally offset, and usually interlinked, Unicode 4.1 character U26A4 ⚤).  Instead of using the clichéd pink-and-blue of recent origin as colors of the sexes, this graphic variation of the symbol uses the colors based on the old "alchemical" assignments of different metals to the seven classical planets (i.e. Venus=copper=patina=green and Mars=iron=rust=red -- see 17101.gif / Rosicrucian Rose.jpg).
For versions of this symbol using the recent (early 20th century) commonly-used colors pink and blue, see HeteroSym-pinkblue.svg and HeteroSym-pinkblue2.svg (or the alternative artistic rendering Symboly Venuse a Marsu spojene k sobe.svg).

For versions of a "planetary" symbol of the sexes with slightly different symbolic meaning, see Sexes-planetary-sym.svg, Sexes-planetary-sym-dimcolors.svg, and Sexes-planetary-sym-pinkblue.svg.
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AnonMoos