Newton disguised himself and went on the streets and found out who was counterfeiting the coins in London.
They look for anything and everything. The garbage of the past provides information about a time and place. It is amazing what they find in sewers. In the City of London Museum I once saw a counterfeit coin thrown away by the counterfeiters hundreds of years ago. It was found in a garbage pile from the past.
Another (of several) feature to help deter counterfeiters, and as a help to people with limited vision.
Issac Newton discovered gravity.
NO newton didn't have help because the apple fell on his head and the thought came to him.
gravity
Your brain.
the laws of gravity
i dont know maybe
Calculus
Just looking at the coin carefully will help. The name of the country might not be in English. For example, a French coin will say Republique Francaise on it, and a Swiss coin will say Confederatio Helvetica. A good coin book will help find the answer.
he thought it was a way to help improve the solar system
Go to a coin dealer or a jeweler, they have tests that will verify if the coin is gold or not.