David: I've used Opticon 224 a number of time and can tell you a
little about it. One caveat first--I have never been satisfied with
the results I've gotten, so I may not be the best source of
Basically, Opticon is a 2-part epoxy. to use it you:
1) Clean the stone thoroughly.
2) Coat the surface with the resin. Alternatively you can immerse the
stone in a pan of the resin.
3) Put it in an oven at 150 degrees F for 1 hour, or until the
4) Wipe the excess resin from the surface.
5) Apply the hardener to the surface
6) Wait a bit and remove the excess hardener from the surface.
The manufacturer claims it will fill pits on the surface. In my
experience, it fills pits as poorly as it fills cracks. I have had
disappointing results with a range of stones including amethyst,
Australian white opal, Peruvian blue opal, nephrite, and sugelite. I
have spoken to a few other lapidaries who have had similarly
disappointing results. Perhaps you'll get better results. If you (or
any other Orchidian) do get good results, please let me know how you
accomplish them and with what stones. Good luck!
and it in the resin for results I was