Can a lower-coloured stone be heat treated to become whiter?

[Phoenix]

I have a 0.90ct H-I IF-VVS1 stone (no certification) that is currently set in a 3-stone ring with two E-F Si1-Si2 1.2ctw sidestones. There's a noticeable slight colour diffrence - even face up - and it hasn't really bothered me that much, but I have to say sometimes I've wondered if this H-I stone can be treated in order for it to go up a grade or two higher (I realise that it must be impossible to go up several grades)?

Also, this 0.90ct H-I IF-VVS1 coloured stone may also be taken out of my existing 3-stone ring in order to match up with a 0.90ct G VVS1 stone (with medium/ strong blue fluor - don't know which), to make into a pair of earrings, or alternatively put into another 3-stone ring (I have another stone, a 1.03ct G VVS1 also with blue fluor). I realise that one option would be to purchase another 0.90ct G VVS1 stone, but am hoping not to have to spend a boatload of money to make this new pair of earrings/ new 3-stone ring.

Does anyone know if there's such a treatment and who would offer such a service and also how much would it likely cost?

ETA: this 0.90t stone may be H-I-J, I don't really know exactly what colour grading it is. My gemologist says it's more likely to be I-J (but I think he's a bit strict with colour grading). It was sold to me as an H; and to my eye, by itself it doesn't really look tinted, only when put next to the E-F stones.

 

[oldminer]

A very small percentage of diamonds, said to be less than 2%, are the right chemical - atomic composition to be whitened, generally from brownish to near colorless. This is something that is very unlikely to be of any use to your H color and very much more likely to be impossible.

 

[Phoenix]

Date: 1/25/2010 8:28:24 AM
Author: oldminer
A very small percentage of diamonds, said to be less than 2%, are the right chemical - atomic composition to be whitened, generally from brownish to near colorless. This is something that is very unlikely to be of any use to your H color and very much more likely to be impossible.

Hi there David,

I was hoping you would chime in. Thanks very much for letting me know (though I''m a bit sad that I''d have to shell out more $$$ to purchase yet another stone

). Your posts are always informative and educational.