Mexican Cantera opals are the equivalent to Australian Boulder opals. They are polished with the matrix which is called cantera.
This one has a little window in the cantera through which you can see the amazing opal colors. I love this stone!
I set it in a bezel knitted from warm golden copper wire with a crochet hook and added tiny pink freshwater seed pearls that pick up the color of the cantera.
A friend said she was reminded of a dragon's egg about to hatch. I bet a dragon from this egg would look just beautiful.