What are the ways to distinguish real diamonds from fake?

Breathing test: By placing a diamond stone near the mouth and breathing on its flat surface, the diamond will distribute heat immediately, so instead of appearing cloudy, it will appear transparent immediately.
• Scratch test: it is done by scratching the diamond with a piece of glass, and based on the degree of hardness of the diamond, the real diamond will scratch the glass, but if it is fake, it will not leave any trace or scratch on the glass.

• The newspaper or paper test: they are used for large diamond stones, by placing stones on the writing or a point, in the event that the vision is clear, this indicates that the diamond is fake, but in the case of not being able to see the writing or the point, this indicates that the diamond is real, due to the property of refraction The light obstructs the view of what is under it.
• Water test: It is done by placing a diamond stone in a cup of water. If the stone settles at the bottom of the cup, this will indicate that it is real. As for the fake diamond, it will float due to the presence of materials of different density in it.