David is a chemist who has developed a method of stabilizing, filling cracks in, and sometimes enhancing the color of the beloved Nevada Opal. See the October 1999 Rock and Gem article, Stabilizing Opal, written about David's work by Bob Jones. Click on the images below, also used in the Rock and Gem article, used with Mr. Lippmann's permission, to enlarge them and get an idea of how good these stabilized opals look once they have been treated with David's process. Previous cracks or crazes are hardly visible. As you can see from the photos above these opals look really good once they have been stabilized.
Previous cracks are almost invisible.
The opals found below are from the Rainbow Ridge Mine of Virgin Valley, Nevada. The treated opals have a shine and can be used in jewelry or as specimens just as they are. David does not recommend that you try traditional cutting methods on these stones, but rather use the stones as they are. None of his stabilized opals have developed new cracks, but a few have broken along prior lines when being cut. He cannot warrant the opals if they have been cut, but will refund the purchase price of an unaltered opal if it breaks within a reasonable period of time.