They most definately won’t be Georgian or Antique diamonds. The Princess cut became popular in the late 1970s.
You would want proper confirmation that they are actually diamonds. Man made gems like CZ or just paste, look like diamonds.
It would obviously make a HUGE difference to the value.
What is the metal?
If it is 18ct gold or Platinium more likely diamonds, if silver or no marks, much more likely man made stones.
The stones could be old cut diamonds or glass.
We need more info and better photos.
Close ups of the stones would be helpful, and photos of the back as well. Are there any markings?
Where did you get it? What kind of metal?
Help us to help you.
This one looks similar to yours, it is silver and paste (glass)
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