You don`t need real ones, the fakes will fool anyone anytime unless it`s some expert looking close.
The only real use diamonds have is for industrial purposes, cutting tools, record players... other than that, all you are doing is wasting a ton of cash on a freaking rock that will never sell for more than what you paid (unless you find a willing sucker).
It`s the ultimate pet rock scheme. If you promote something enough, people will buy anything.
Nope, diamonds ( or any other gem stones ) are not the equivalent of a "pet rock".