If you rub a real peal across your teeth--it doesn't squeak. Like a real diamond will etch glass.
Here is a really great resource that should answer your question and good luck!
Believe me, a fake pearl looks nothing like a real one
How do you define as real cause some companys put a little pice of rock or marble to start the Perl making process cause pearls are made when something is introduced into the "mouth" of the oyster that should not be there and the oyster will put a coating on in efforts to eject the unknown ob
but real pearls are made then the oyster eats something and some sand gets in there these are called natural pearls and the most expensive but are the most beautiful.
the cultured pearl will have a lot bigger more dense core than a natural pearl
cultured pearls are like gold plating and real pearls are like 24 kt
so to be able to differentiate in between the two you would most likely have to x ray them....
The "teeth test" is no longer valid, as many companies now apply artificial nacre over resin
"pearls". Generally, the more dissimilar they are, the more likely they are to be real. Under strong light with a magnifying glass, you will notice irregular ridges and valleys. Th higher degree of variation, the greater the likelihood that they are real.
Trust me youll know when its real compare at a jewelry store their shine has a creamy depth to them i was told that pink pearls are not real but i still want a certain pink pearl ring.