Ruby
Rubies have been sought after since ancient times because of their lively red color. Almost all rubies have been heat treated to lighten or intensify color, or to try and improve clarity. Since about 2001 most African rubies have been treated with Beryllium diffusion to improve color. This treatment is not effective with Burmese rubies, so at this time it can be assumed that rubies with inclusions indicating Burmese origin are not treated with Beryllium.
Treatments: Heat treating is almost universal, Beryllium diffusion in African rubies, and fracture filling.