Diffusion treated sapphire

[Ziggy85]

Hi,

I am trying to create an elaborate necklace for myself.

I found these guys in Thailand that say they have lab grown sapphire that are "diffusion treated" for $9 per carat. I am looking at 19 carats, so it's going to be $172 for this.

I just read about diffusion treatment, is it worth it?

 

[deorwine]

$9/carat is pretty good for such a large stone, even factoring in that it's artifical and treated and whatever. I'm not sure you could do much better with anything else. (Even just a plain flame fusion sapphire, if I understand correctly, because the flame fusion rough color is uneven it would be hard to cut a stone that large with even color. Though would love to see a cutter weigh in on this!)

Also since it's a necklace the fact that diffusion is a surface treatment won't be a problem (whereas in a ring that got knocked around more maybe that might be a consideration).

The other thing you should consider is that I would bet money the stone in the pic has a large window. IDK if that would bother you (it doesn't bother some people; it would bother me), and it's probably also a function of trying to get as large a stone as possible from their rough.

ETA: Wait, nope, that is on the expensive side (and I've struck through the text to indicate that). I'll comment again but I wanted to make sure I amended this one.

 

[deorwine]

I went and looked at a vendor I have used recently on Etsy for lab/diffusion stones and they have much cheaper prices:

Oval is $52 for 18mmx13mm

Cushion is $52 for 16x12 (out of stock in larger size)

Unfortunately the largest emerald cut they have is 12x10

I have bought stones from this vendor and like them, though the ones I've bought have been on the smaller size. I will say the color is pretty nice (the Etsy pics are of course glamour shots but they look pretty good in person as well), but the cutting on these IS quite windowed and in general not really at all "precision" quality, if that's something you care about.

What I said about diffusion treatment and how it is a surface treatment (so is probably not a problem for a necklace) still applies, though.