This list digest contains the following message subjects:
1. NEW: IMPORTANT How to reply to a message.
2. Re: Technique to Fill Flaws
3. Re: Technique to Fill Flaws
4. RE: Techniques to Fill Flaws
5. RE: jelly opal
Subject: NEW IMPORTANT: How to reply to a message.
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Date: Sun, 15 Jun 97 14:05:10 PDT
Subject: Re: Technique to Fill Flaws
Brad, use Hot stuff for all your filling needs . There is three viscosities
available from runny ( for thin shallow cracks ) to very thick ( for pits,
and bigger, deeper holes) . I use it exclusively. About $10.00/4oz bottle.
All but the runny last quite a while for me. I do an awful lot of work.
Frank for Rough&Tumble
Date: Sun, 15 Jun 97 20:53:38 PDT
Subject: Re: Technique to Fill Flaws
Brad Smith wrote: "<snip>... I stopped after the 600 grit sanding
(so as not to get the surface flaws filled with polish) and treated
the area with Opticon. But when I tried to lightly re-sand the
surface, the porosity came right back. Any ideas? "
First clean stone in acetone or alcohol. Wait until it is dry before
starting with the opticon. The hour or so at 150 F seems right for
penetration. Make sure you cool off slowly. I usually mix the stuff
1 drop of hardener to 7-8 drops resin, coat the stone completely,
wait about an hour then gently warm in oven - 150 F again for
about an hour. Again cool slowly. The instructions also allow for
applying a drop or two of hardener to the stone then wiping off in
about 5 minutes. The stuff isn't perfect, but it does help in some
Hope this helps some.
Date: Sun, 15 Jun 1997 21:12:14 -0700
Subject: RE: Techniques to Fill Flaws
>But several other attempts did not turn out as well. For instance
>on a piece of silver onyx, the areas of a pretty iron colored stain
>were a little porous and would not produce a good surface finish.
>I stopped after the 600 grit sanding (so as not to get the surface
>flaws filled with polish) and treated the area with Opticon. But
>when I tried to lightly re-sand the surface, the porosity came right
> - Brad Smith
Opticon won't soak into most rock, it is intended to fill cracks and small
cavities which it does reasonably well. With a porous surface you will
have better luck polishing the cab after the Opticon (or any other good
epoxy, that is all Opticon is, it just has the viscosity optimized for
filling cracks) has hardened. Just remember you are polishing the epoxy
not the rock.
For polishing very soft materials such as plastic, stabilized turquoise,
or epoxy I have had the best luck with ZAM on a soft cotton buff. If
any of you have had better luck with some other technique please share
information with us.
Date: Mon, 16 Jun 1997 02:30:42 -0400 (EDT)
Subject: RE: jelly opal
<<I got a few nice pieces of jelly opal in a trade the other day.
about the size of lima beans. Since I have never worked with opals, where
do I begin?
I've not had any problem with heat sensitivity with these stones, but
that they are hydrous in nature, do take care not to overheat. Here I'm
assuming that you're going to cab cut. Dop as usual, preform on no coarser
than 325, if possible; newer 600 will work. Pre-polish on worn 600, polish
with cerium oxide on leather. Don't suggest trying to cut calibrated stone,
just follow the natural contours to increase your return. Let us know
you make out!
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