Dyed Chalcedony Imitation of Chrysocolla-in-Chalcedony
Chrysocolla-in-chalcedony, also known as gem silica or blue chalcedony in Taiwan, is the most valuable chalcedony variety on the Taiwanese market.
Solid Carved Dark Gray Diamond Ring
A ring made entirely of natural diamond was recently submitted to GIA’s New York laboratory.
Color Classification and Stability of Queen Conch Pearls
Color stability experiments show that the color of Queen conch shell and pearls may shift in hue and/or saturation under X-ray radiation or short-wave UV radiation.
