Posted by Henry Barwood on September 12, 2000 at 12:47:30:
In Reply to: synthetic/artificial opal posted by Henry Barwood on August 18, 2000 at 11:43:01:
I'm going to do a follow-up to my own post here. I've been in contact with a number of people who are interested in opal synthesis.
After a review of the patent and published literature on the subject, I've concluded that many details of opal "synthesis" are kept deliberately
vague (big suprprise). Growing the monodispersed silica spheres for the opal turned out ot be the easiest part and I was able to make a
beaker full on the first try. Hardening them is another matter entirely. There seem to be only a few types of hardened "opal" on the market: 1)plastic infiltrated
2) hot pressed (Gilson?) 3) zirconia reinforced sintered (Kyocera) and 4) silica gel reinforced and sintered (Russian and Japanese?). None of these
methods exactly duplicates nature, but produce a marketable product. I hope to test some ideas I have on generating a more natural opal, but this
will take a while since it is not what I do for a living (!). Anyone with additional information on synthetics is welcome to e-mail me. Thanks.
Henry
...........................
: I am interested in "synthetic" or "artificial"
: opals (excluding the plastic impregnated ones and
: "Slocum stone"). Besides the Gilson opals and
: Kyocera "opals", does anyone know of any other
: manufactured "opals". The Russians wrote a book on
: creating opals, but I cannot read Russian, so I don't
: know what they document, but I've heard that they sold
: the process to a company in Japan. Can anyone who is
: knowledgeable in this area clarifiy who exactly is
: manufacturing opals. Thanks.