Grotto - Mexican Matrix Fire Opal

"Grotto" weighs 9 carats and is 3/4" long. Intense blue and green opal is locked deep within the matrix of this stone, reminiscent of a magical grotto. I envision a ring with an ocean theme, but perhaps a dragon would like to guard this grotto? The 18K gold ring, when completed will range somewhere between $3800-$4600.