White Mare, Inc. was a feminist Lesbian button company owned and operated by Liza Cowan, co-editor of DYKE, A Quarterly. This image of the Chai inside a Labyris was very successful, so White Mare made it into a limited edition rubber stamp in addition to two runs of buttons.  

This design combines several powerful words and symbols: the Star of David (a cross -cultural geometric symbol- here indicating Judaism,) the Chai, the Hebrew number 18, which is good luck and other resonating numerology .The Labryis, the double headed axe, symbol of Matriarchy and Amazons. The circle sitting atop the Labyris, turns it into a Venus or women's symbol. 

More about White Mare buttons HERE