Are black diamonds severely flawed diamonds?

[dertaika]

Depends on what you want them for. Since they are not optically transparent, and tend to have a lot of stacking defects, they are no good as gems. They are no good for optical applications either. But black diamonds are tougher than most diamonds since they contain graphite and amorphous carbon. They are also polycrystalline (meaning, instead of being a single crystal they are made up of multiple crystals). Black diamonds could be used for other applications.

[JohnStaples]

Hello! Help please, I found a site where a lot of black diamond tennis bracelet are sold. Is it worth it to buy such jewelry from them? If anyone has purchased from them please share your experience. I just want to make my girlfriend nice and give her some kind of decoration. Since she really loves bracelets on her hand, I decided that this would be the perfect gift.