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Repairing scratches in stones


#1

Dear Friends,

Is there something I can use with my flexshaft to repair scratches
in stones that were caused during setting. Today I set a tourmaline,
a peridot, two opals, and a blue topaz. I scratched two with the
setting hammer and the others with the burnisher. It was one of
those days I shouldn’t have been in the studio at all. I’d love to
be able to polish out the scratches and repair the pieces. The
thought of wasting all that work just kills me.

Thanks for your thoughts,
Karin


#2

To remove surface scratches in the stones you mention, try a hard
felt buff in your flex shaft and Cerium Oxide with a bit of water.
Let us know how you do.


#3

Karin, the type of “scratches” one gets from accidental contact with
setting hammers and burnuishers are generally deep enough that minor
polishing while still set won’t do the job on facetted stones.
You’ll most likely need to cut them back out and have them properly
repolished. The reason is simply that nothing you can do with, say,
a flex shaft, will give you a poperly flat facet, and the little
wavey curved surface you’d get trying to take out the damage won’t
look much better than the damage itself. Now, your opal, or other
cabs, on the other hand, can be helped, though it’s not usually quite
as good as removing the stones and repolishing, since usually the
damage is right next to the bezel metal, and you can’t get in there
and feather it into the existing surface perfectly. But for the
opal, there are a number of rubber wheels that will do the job,
including some that use diamond as the imbedded abrasive (Stuller or
Rio carry them, among others. They’re pricey, but last quite a
while). Also there are a number of such wheels that use aluminum
oxide or silicon carbide abrasive, and the very fine semi-polish to
polishing grits will often help minor scratches in soft stones. Or
use a bit of cerium oxide, wet, on a small felt wheel. Or lapidary
diamond paste compound on that same wheel, etc.

Peter


#4

Karin,

Indeed, it sounds like you had a bad hair day!!

Unfortunately, you are talking about apples and oranges. The opals
might possibly can be touched up with the flex but only if you have
experience working with stones. Opal can be cantankerous and
subject to crazing if heated. So…be careful not to overhead. If
the scratches are shallow, you might try using SOFT felt wheels and a
very light touch. Of course, if the scratches are near the bezel,
you might end up changing the shape of the bezel as well. If the
scratches are deep, the stones will require complete recutting and
must first be removed.

The tourmaine, peridot and topaz are a different story. Assuming
they are faceted, they must be removed and recut on a faceting
machine. I suggest strongly against trying to remove scratches on
faceted stones with any kind of rotary wheel. The facets will become
rounded and the facet meets obscured. Result will be an ugly stone.

Sorry looks more like ‘a learning from your mistakes session’ than a
waste of work.

Cheers from Don at The Charles Belle Studio in SOFL where simple
elegance IS fine jewelry! @coralnut2