By Ted Grussing
… Jim came over a few days ago and took some photos as I began the process of converting a very beautiful piece of opal rough into a couple of museum quality stones. This piece of gem quality rough opal is from the Olympic Fields in Coober Pedy, SA and came out of the ground back in the early 50’s and it is one of the larger pieces of gem quality opal rough I have seen. It weighs in at close to 20 Troy oz. and is pretty much solid color bars. A pretty good article on opal can be found at https://en.wikipedia.org/wiki/Opal Opal deposition according to some sources occurs at a rate of about 1 cm per million years which if true makes this piece of rough a gem some 3 million or so years in the making. The Olympic Field was noted for the stability and beauty of the gems it produced.