New Boron heat treatment of Blue Sapphire ?

[MingmehDorji]

Hi,

Is it true that there's new Boron infused heat treatment of Blue sapphire already in the market ?

Please click link : http://www.themelis.com/A-News.htm

Dorji.

 

[rubydick]

According to information provided to me by a friend:

"Boron (B3+) is isovalent with Al3+, and thus does not cause the formation of trapped holes or other types of light-absorbing point defects in sapphire, as would Be2+ or Mg2+. Boron oxide, B2O3, is also colorless, so B3+, substituting for Al3+, produces no color. Since B3+ is isovalent with Al3+, it will diffuse very slowly in sapphire, somewhat like the self diffusion of Al3+ in sapphire (imagine that one used a different aluminum isotope so you could tell the Al3+ ions apart, which is the way the experiment is actually done). B3+ is smaller than Al3+ so it will diffuse somewhat faster that would Al3+, which means that it is probably about 100 times slower than Ti4+. Because of the size
mismatch, the solubility will not be high.

"Boron is almost always used in Thai heat treatment as boric acid or borax (sodium borate) which is part of the flux mixture. Thus there
will be boron on the surface and in the cracks, but very little will diffuse into the stone."

In layman''s terms, the rumors of boron diffusion in sapphire influencing color would appear to be greatly exaggerated. But that said, I try to keep an open mind. If someone can emperically prove otherwise, I''ll be happy to adjust my opinion.