Hello Patty; Long answer here.
My guess is that yes, you have indeed overheated the stones.
Problem is, the charcoal block was not a good choice in this case.
Charcoal is carbon and carbon is fuel. You probably didn’t realize
how hot the ring was getting. If this ring was thin, as I suspect
(being set with .03 carat stones) it wouldn’t take much to overheat
it. If it’s an old mounting and was set with single cuts, those are
all the easier to overheat. If you can carefully lift back the
channels, you can re-set the ring with new stones. Here’s what I
would do if I were in your shoes.
First, inform the customer what happened, that things like this do
happen occasionally, and that you will correct the situation to their
satisfaction. You will need to buy a little more time, but prioritize
this. Second, if you can’t peel back the channel to remove the
stones, you will have to grind away one side of the channel and
remove the stones. You can sell them to a company that buys damaged
stones, but I don’t know what you can expect to get for them.
Perhaps someone on Orchid has experience in this area. You could ask
about having them re-polished and if this was cost effective, when
you re-sell the re-cuts, you’ll recoup some of your loss. Remember,
you’ll be buying the new stones wholesale and selling the re-cuts at
Now, carefully fit in a piece of platinum to replace the area of the
channel you’ve ground away. Here’s the most important part. . . .
Lose those old platinum solders! Call P.M. West or one of the other
refiners and order some of the new platinum plumb solders, at least
the hard and easy. They’ll cost around $50/dwt. These melt at
around 1350 C instead of the 1700. You can use your old solders for
some kinds of fabrication, but once you try the new solders, you’ll
never to back to them for sizings. Get a ceramic soldering pad
designed for platinum work, and a titanium solder pick or some
ceramic tipped tweezers. It’s crucial that you not have any gold or
steel in contact with the platinum when you’re soldering. Platinum is
not a particularly good conductor, so it’s sometimes possible to keep
stones protected by keeping them under water when you heat. I often
use wet sand to hold up a ring while soldering (but it’s clean sand,
no metal filings). Use the hard grade of platinum plumb solder to
solder in the new channel wall. You’ll have to have a slight “V” at
the seam since these solders don’t flow as easily as gold solders.
Heat a little at first, then stop and examine the ring to make sure
there is no other solder work in the area. If there is, you’ll be
going to plan “B”, I think. I know you don’t have a laser, or you
probably wouldn’t have been sizing with a torch. After you’ve dressed
up the channel, then re-set new stones. You’ll spend about $250 for
the new stones, maybe less if you have a good source for melle=E9.
If the customer isn’t satisfied, or you don’t like the job when it’s
finished, you may have to order a new mounting, or carve a wax and
cast (or have cast) one to match (plan “B”).
There is no easy way out, but you can use this chance to solidify a
relationship of trust with a customer, and when you do fix this to
their satisfaction, you’ll have bought the best lesson in how to
build trust and confidence in your customers and you’ll look back and
realize it was a bargain. The truth is tough, but it has power.
Good luck, write me if you have any questions.
David L. Huffman