How rare is this ruby?

[TKC]

How rare is this ruby and how much the cost per carat? Sorry only the report

 

[TKC]

Why there is not any iformation about heat enhancement? I see one of the AGL grading report mentioning "heat enhancement: ......" and "clarity enhancement: ......"

Here is a sample of the AGL lab. report from the precious gemstone website that you can see:
http://www.preciousgemstones.com/112burucert.jpg

The colorscan is similar on both stones, the only different is that one has clarity enhancement (faint only) and the other one is none according to the AGL lab. And, the cutting, tone and clarity grade are a bit different. The size is a lot different.

 

[MJO]

There is know mention of heat enhancement because it is heat enhanced. All Ruby from that section of Burma comes out of the ground dark purply blue and is heat treated to bring it to a saleable color. Also alot if it has glass in the stone to improve the clarity and as a residual from the heat enhancement.

 

[TKC]

Date: 7/14/2005 9:35:55 PM
Author: MJO
There is know mention of heat enhancement because it is heat enhanced. All Ruby from that section of Burma comes out of the ground dark purply blue and is heat treated to bring it to a saleable color. Also alot if it has glass in the stone to improve the clarity and as a residual from the heat enhancement.

Isn''t it that most of rubies even from Mogok are heat treated to improve their color. Is it possible to heat treated dark purplish blue color into beautiful red (saleable color) beside using Beryllium?

 

[TKC]

Does anyone know the prices of Mong Shu rubies compare to Mogok ones?

 

[TKC]

By the way, what does it mean by "faint clarity enhancement (inorganic type)" on the report? I hope someone/expert who is familiar with the AGL lab. report can help me to explain it. Thanks

 

[Richard Sherwood]

Hi TKC. I'm not certain why the AGL report doesn't mention heat treatment for color enhancement, as virtually all the Mong Hsu rubies are strongly heat treated to remove the bluish core/tint, as MJO mentioned.

The "faint clarity enhancement of inorganic nature" would be faint glass or flux residue, either deliberately introduced or as a by-product of the heat treatment (also as MJO mentioned).

The Mogok mine is known for producing rubies which often don't need color enhancement, but is not producing near as prolifically as the Mong Hsu mine. Most the "classic Mogok" rubies on the market are from older estate pieces.

The price differential between an unheated classic Mogok ruby and the usual heavily heat treated Mong Hsu ruby is substantial, especially in carat plus stones, and even more so in 2 or 3 carat plus stones. Big difference.

 

[Richard Sherwood]

Date: 7/15/2005 12:56:03 AM
Author: TKC

Date: 7/14/2005 9:35:55 PM

Is it possible to heat treated dark purplish blue color into beautiful red (saleable color) beside using Beryllium?

Yes, it's possible, and quite common. Probably 90+% of the rubies mined in the Mong Hsu district are treated in this manner.