Are my " diamond " tweeters really diamond


Could my diamond tweeters be coated with zircons and not real diamonds. I paid a lot of extra money for those diamonds.

soundsrealaudio
Ruby, sapphire and diamond phono stylus cantilevers are all man made. The later being made with corundum, which is an aluminum oxide. Why would tweeter domes be any different?
vapor deposited on cone made from another material so more like diamond coated