Mozambique Ruby - low heat treatment

[Marlow]

http://www.gia.edu/cs/Satellite?blobcol=gfile&blobheader=application%2Fpdf&blobheadername1=Content-Disposition&blobheadername2=MDT-Type&blobheadername3=Content-Type&blobheadervalue1=attachment%3B+filename%3DMoz_Ruby_LowHT_US.pdf&blobheadervalue2=abinary%3B+charset%3DUTF-8&blobheadervalue3=application%2Fpdf&blobkey=id&blobtable=GIA_DocumentFile&blobwhere=1356006488184&ssbinary=true

A very long but very interesting article about low heat treatment of ruby from Mozambique.

Esp. the before and after pics are really great!

 

[dk168]

Very interesting read, thanks for sharing.

DK

 

[evergreen]

Really interesting, even to those of us without a technical/gem-educated background... but in looking at the samples where the blue or purple element was "clearly" diminished, I was reminded of that can-you-see-the-color-change test...

 

[Marlow]

Really interesting, even to those of us without a technical/gem-educated background... but in looking at the samples where the blue or purple element was "clearly" diminished, I was reminded of that can-you-see-the-color-change test...

Me too!!!

And sometimes I wonder why the heat them course it was only a tiny amount of blue. So a little bit better heated color versus unheated....

 

[Dioptase]

And sometimes I wonder why the heat them course it was only a tiny amount of blue. So a little bit better heated color versus unheated....

Purplish in ruby / sapphire isn't really desirable. The market want pure pink or red. That's why they heat so much light purple sapphires from Ilakaka to turn them pink. Easy to sell.
Now, for the ruby case, it might be because sometimes the seller won't say the rough has been heated. And if the lab can't find clues of the treatment...

 

[Dioptase]

Forgot to add:

Really interesting, even to those of us without a technical/gem-educated background... but in looking at the samples where the blue or purple element was "clearly" diminished, I was reminded of that can-you-see-the-color-change test...

I must say the change was more visible on the large pictures projected during Vincent's speech at the GIA gathering.
Also, the light just goes through the wafer sample; in a faceted stone the light would travel differently and the result would be much more visible.

 

[Marlow]

Forgot to add:

Really interesting, even to those of us without a technical/gem-educated background... but in looking at the samples where the blue or purple element was "clearly" diminished, I was reminded of that can-you-see-the-color-change test...

I must say the change was more visible on the large pictures projected during Vincent's speech at the GIA gathering.
Also, the light just goes through the wafer sample; in a faceted stone the light would travel differently and the result would be much more visible.

Then I understand - thank you for this info...