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Recutting cracked doublet

Cracked a boulder doublet. opal top…ironstone back. Anyone had
experience either having a doublet recut or recutting same.

Would appreciate advise

Richard W. Wise


I’ve cut opals and assembled doublets and repaired a few of each — it
would probably help to have very good magnification so you could see (try
to see, it’s tricky) how deep the crack is and whether it goes into your
primary fire layer. Obviously if the crack goes into that layer, you’re
going to be grinding away who knows how much of your fire. Since Paul
Downing, the primary opal valuation authority, says cracked opal is worth
just about nothing, in many cases you should grit your teeth and see what
you’re left with.

I don’t know what your particular boulder doublet looks like. The ones I
have and have seen at shows that are backed with ironstone have a very
thin layer of opal which is flat. I think it’s unlikely that you’ll get
the crack out without going most of the way thru the fire layer. Might be
better to cut the stone along the crack, if the crack is fairly straight,
and end up with two stones. I’ve seen pretty good doublets for about
$8/carat at shows, so perhaps it’s not worth it . . . If you just want to
get rid of the crack you might try putting some Opticon on it. The
doublet usually isn’t that valuable anyway, unless it’s just the best
stuff there is. The Opticon won’t decrease the value of a cracked piece,
but if the appraiser sees it (and he should) it’s still valued as cracked


Cracked a boulder doublet. opal top…ironstone back. Anyone had
experience either having a doublet recut or recutting same.

Cracked or broken, doublet, overlay or boulder, there is only the one
option and that is to saw through the crack(s) and cut and polish the
Luckily freeform opals are quite acceptable, even very small ones are
valuable if they are pretty enough and you now have a matching suite.
Because Opals are soft and amorphous they are easily worked and hand tools
can accomplish this. Unfortunately it’s these same properties that get
them into trouble in the first place which is why they need special care
and attention always, and should be kept out of rings.
Anthony L. Lloyd-Rees,
Vancouver B.C. CANADA

I have had limited success using Opticon epoxy resin for hairline cracks
in doublets. It won’t work for chips though.

Wendy Newman

Questions, is it a doublet ? Or just a backed stone. And if a doublet, is
the top truly Opal or in a lot of cases, just glass. These have to be
known. Next question. Is the crack in the opal or the top. From these
answers I may be able to help you. I have cut and made doublets many times
from thin slices of fine Opal. And made numerous repairs of other peoples
work. The latter being the hardest, not knowing exactly how they were
made. Can you scan and send me a picture? Steven