All, An alert for all. A gemstone dealer I know has just received a
parcel of the best top blue sapphires you have ever seen. At a
price that was much lower than what they should have cost.
Accompanying the stones was a certificate from a USA gemstone
laboratory that stated the stones were natural and only heated.
Suspecting something was astray, he checked them out and discovered
that the stones were diffused. Special techniques of immersion,
magnification, and a life time of sapphire knowledge were needed to
detect the treatment. He sent the stones back to their source along
with an explanation of what he had found. Diffusion is becoming
almost impossible to detect. Beware of deals too good to be true.