This is GIA's findings on a rare treated fancy red diamond that rivals natural. Gorgeous!:
Treated Fancy Red Diamond
Paul Johnson and Christopher M. Breeding
GIA Laboratory, New York and Carlsbad
"Natural-color red diamonds are among the rarest and most prized of gemstones
and command some of the highest per-carat prices in the market...."
"Recently, GIA graded a 2.14 ct oval cut diamond (figure 1) as Fancy red and
determined that it had undergone color treatment....
http://www.gia.edu/research-resources/n ... iamond.pdf
