Mike, first be certain it's a synthetic. this should be a "no
brainer" ID, but be sure. Among other things, i've seem some glass
products that at first glance seemed similar, which are more fragile
than the synthetic corundum (sapphire) common synthetic.
If the stone (unlikely for that size) is a true synthetic
alexandrite, then it deserves particular care since unlike the cheap
corundums, it's a bit pricey and might be hard to replace. And it
likely will not respond well to retipping. just remove it for the
But for what you describe, it's mostly likely the cheap corundum
Either way, I'd not recommend retipping directly on the stone.
Corundum itself can take the heat, but you'd need to be very careful
to avoid contacting the stone with flux at soldering temps, as that
can etch corundum, and you'd need to use a torch flame that was
neutral to slightly oxidizng, again to avoid chemically altering the
aluminum oxide. It CAN be retipped, if you're careful, but
understand that it's a bit risky. These stones may be under some
strain, and even if you don't damage it with flux or the heat, they
can crack. So you'd need to be very careful and gentle with slow
heating and cooling rates.l. Sometimes it's possible to pull a
damaged prong away from the stone so there's a millimeter gap between
the worn prong and the stone, which makes it then much simpler,
especially with a very tiny torch, to get some more metal on the tip
without overheating the stone. Be ready for the stone to
dramatically shift color during heating. don't worry, when it cools,
it comes back.
But if you're unsure of this, or don't wish the risk of having to
spring for a new stone (probably cost you 25 bucks or less) if you
damage it, then just remove the thing. that's the safest way to go
on a number of issues.