Lay the stone onto the dot with the flat side down. Through the pointed end of the diamond, look down onto the paper. If you see a circular reflection inside the gemstone, the stone is fake. If you cannot see the dot or a reflection in the stone, then the diamond is real.

How can you test a diamond at home to see if it's real?

This one's easy: Get a glass and fill it with water (it doesn't matter what type of water you use). Drop the diamond into the glass of water. Due to the high density of diamond, when dropped into water a real diamond will sink. If the diamond floats to the top or middle of the glass, it's fake.

How do you test a diamond sparkle?

A sparkle test is quick and easy to do since all you need are your eyes. Simply hold your diamond under a normal lamp and observe the bright shimmers of light bouncing off the diamond. A real diamond provides an exceptional sparkle since it reflects white light extremely well.