Apparently, there are physics involved in this test. (You can read about more tests, below.)

On a clean, dry diamond, use a pin to drop a tiny amount of water on the table -- top -- of a cut diamond. If a diamond, the drop will maintain its shape; if not, the drop will flow off the table.

No matter how big the weight it will never be able to crush the diamond.

High quality companies such as De Beers, Cartier, Tiffany and Anne Klein offer special designer lines of diamond drop earrings available in stores and online.

Find the oldest hobo you can & ask him to drop his draws...

Yes. I have a Super Drop Diamond stashed in the parking space outside Playboy X's apartment (you can use Niko Bellic's parking spaces from GTA IV), and another Super Drop Diamond spawns outside of Yusuf Amir's place.