Research & News
A large tanzanite loses its appeal with the removal of its fracture-filling oil.
GIA Knowledge Sessions
Engage in webinars on the most diverse and pressing issues in gemology today, including gemstone origin, laboratory-grown stones and new discoveries in field gemology.
What Have Diamond Ages Taught Us?
Diamond ages offer insight into continent evolution spanning billions of years.
Zircon in Jadeite Jade
A doubly terminated zircon inclusion survives multiple treatments in a translucent bangle of jadeite jade.
Spectral Analysis of Resin Imitation Ivory
Spectroscopic techniques prove key in separating resin-based imitation ivory from natural ivory.
Rare Intense Purplish Pink Montana Sapphire
A Montana sapphire of unusual size and color proves to be from the secondary deposit of Rock Creek.