New Synthetic Rubies Made by Professor P. O. Knischka
E. J. Gübelin, September 1, 1982
A new synthetic ruby is discussed.
Read More
Ruby and Sapphire Production and Distribution: A Quarter Century of Change
Russell Shor and Robert Weldon
During the past 25 years, the corundum market has been transformed from one of medium to high-priced gems to one that encompasses nearly all price ranges.
Read More
