It is possible to use physical tests to help determine whether a jade is real or fake, but there is no full certainty from these. Here are a few common physical tests:
Hardness Test: Jadeite is a relatively hard stone, with a hardness of 6.5 to 7 on the Mohs scale. If you scratch the surface of the stone with a sharp object and it leaves a scratch mark, it is likely not genuine jade.
Density Test: Jadeite has a higher density than most other stones, so it should feel heavier than other stones of the same size. You can compare the weight of the stone to its size to get an idea of its density.
Sound Test: When you gently tap a real piece of jade with a metal object, it should produce a clear and musical ringing sound. A fake piece of jade may produce a dull or flat sound.
Thermal Conductivity Test: You can hold a piece of jade in your hand for a few minutes, then place it on your cheek. If it feels cool to the touch, it may be real. If it feels warm or room temperature, it may be a fake.
Polarizing Filter Test: Jadeite is known for its pleochroism, which means that it can show different colors when viewed from different angles. If you view a piece of jade through a polarizing filter, you should be able to see this effect. A fake piece of jade may not show this effect.
It's important to note that these tests are not foolproof, and it's always best to consult with a reputable expert or gemologist if you are unsure about the authenticity of a piece of jade.