A lot of jewellers think that it is impossible
The problems that jewellers have in resizing rings with soft stones such as coral, pearl, opal and many others is that they will be instantly destroyed by heat from a jeweller's torch. Diamonds, rubies and sapphires can have a jeweller's torch actually touch them and they will not break. Of course this is always avoided if possible. But many other stones, even emeralds, will have to be removed from the ring in order that the heat from the torch can be used to solder two parts together.
That presents a further problem when the stones have been bezel set. Bezel setting involves the metal being forced over the stones and pushed and rubbed over. This is a one way action and you cannot prize the metal back, take out the stone, and later after the soldering has been done, replace the stone and push the bezel metal over it again. This metal is now ruined.
So what if you could leave the stone in place and cut the ring and then remove a piece making the ring a smaller size and then solder it back together again? Well, that would be just perfect and you can almost do that with laser technology.
With a laser welders which currently costs between $30,000 and $50,000 you can leave the stone in place and make the resize and then weld or fuse the two pieces together. The reason that this can be done successfully is because the laser only makes a tiny bit of heat. You can hold the ring in your hand and laser weld it together.
Lasers can be used on all types of metals titanium, stainless steel, platinum, silver and gold. The laser weld is actually a fusion of the two metal parts so no solder or messy flux is used. The weld is three times stronger than the best soldered joints.
Tiny pieces can be welded together as small as 0.2 of a millimeter and that's small. Most white gold is rhodium plated to give it that shiny white look but when it is repaired it has to be rhodium plated once again but not with laser technology as the weld is a very localized one.
For me to solder two rings together side by side to make a double band it would take about twenty minutes to do the soldering by the time I made some preparations. Then I would need to leave it in an acid bath and then a de-acid bath and all sorts of other procedures to clean it up, so a lot of time is taken. To laser weld the two pieces together it might take three or four minutes and there is no follow on treatment.
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