We had a natural black boulder opal from Australia that reminded us of looking out the window of an airplane as it landed in St. Thomas, USVI ,so we thought it was a natural as a pearl clasp. The opal (31.50ct) is the color of the Caribbean around the Virgin Islands complete with a beach and the sunlight reflecting off the wave tops as you move it. We mounted in 18 and 22 karat gold and it can be used as a clasp on anything and as a pendant on a chain.
SOLD