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How are treated black diamonds made black? Why do they test as moissonite?


I am looking for something with a citation here if it exists.

  1. I know that black diamonds are treated similarly to HPHT, I have been told by some that there is a coloring agent introduced, and have been told by others that there is not. I can’t find any articles on the subject with more than an opinion.

  2. Treated black diamonds test as moissonite on moissonite testers (but test as treated black diamonds from labs like IGI or GIA). Treated black diamonds also weigh more than ‘white’ diamonds do with the same measurements. (IE: They have a higher specific gravity)


I have read that the stones they use are so heavily included that they test as moissonite because the crystal structure doesn’t read like normal diamonds, I have also been told that this is the reason they have a higher specific gravity.

Again, I haven’t found anything other than opinion on the subject.