I remember in an interview, I'll definitely post a link if I can find it again, Bernie goes into detailing about Jade dying and diffusion/heating in corundum. He said that it's cut out of the show because travel channel is more about the locations and the people than the technical aspects of the gems. In that same interview Dianne spoke at length about how she avoids dyed jade and how much it devalues it. I think it's called Gem Hunt New Show Interview, it's by some not too well known youtuber. Haven't been able to see it yet, but I'll keep checking.