This beautiful Agate has some lacy patterns and plumes of Marcasite.  It has been wrapped in a frame of sterling silver wire that has been hand twisted to add some interest and to reflect the light.   Pendant measures 2 3/8 x 1 1/4" and hangs from a black leather cord.
 
Even though Marcasite isn't rare, the combination of it with red agate is quite rare and this cabochon has both.