As with many metals and gemstones, a little scratch can do wonders when it comes to figuring out if a pearl is real. Using the tip of a knife, create a tiny impression in the surface. A real pearl will yield a small amount of dust or powder, while coated beads will reveal the surface of the glass. If you choose to go with this method, be careful to safeguard against visible damage. For pearl rings, aim for the back of the pearl, and if it’s a necklace, choose a less noticeable pearl near the clasp.