Hi, I’m just pondering if a prong get work hardened and the stone is already in place.
Can it be anealed in an Argon atmosphere by induction without affecting the diamond or the polishing of the metal?
Bear with me, sometimes my mind wander off and end up with these kind of questions.
Diamonds can go in the fire as long as they’re coated with a good layer of boric acid to protect them from oxygen. Similarly, the polish on the metal will not be affected if the boric acid coating is uninterrupted.
Mix up a thick paste of boric acid (not borax) and denatured alcohol. Apply it and let the alcohol burn off leaving the boric acid layer. Then heat the piece slowly until the boric acid melts and forms a glass. Then you can increase the heat and anneal the prongs.
Allow the piece to cool slowly. Keep it away from possible breezes or cold air from an AC unit. Diamonds, while resistant to heat, can crack from thermal shock, so be sure that it can cool down gently.
This is also how one can retip worn down prongs with solder while still keeping a diamond in the setting.
Best to practice with the boric acid first on a bit of polished metal without stones, to get the hang of it.
What I described and pondered was an inert Argon atmosphere, is Boric acid needed then?
Will the induction heat the Diamond?
Induction will heat the diamond and may change certain aspects of it.
Here’s a little article describing one company’s experience.
But this was done for a prolonged time and significantly higher temps then what is needed for annealing. And it seem to be done with a graphite susceptor, at least according to the pictures.
And as far as I can see on the net, the diamond itself do not heat up in the induction field due to its electric insulating properties.
So I guess it should be safe, if ever the need presents itself.
I agree with the previous post that diamonds are not electrically conductive and are not going to be heated by induction. The example about a diamond heat treatment uses a crucible heated by induction as we can guess by the picture. I have experience soldering jewelry using induction and it is not an intuitive process, if you subject an entire piece to the magnetic field large parts will heat first and small parts after depending of the orientation in relation to the field. Just my opinion is that induction works best with simple parts either small or large but not cluster of dissimilar sizes. Induction heating is an industrial process and should not be considered as a solution to any problem solvable with conventional jewelry tools. Induction can make a very difficult job for a conventional technique very easy for unskilled labor due to its very precise application of heat.
Thanks for the reply, I did not consider uneven heating.
Anyway it is just an imaginary scenario.