Fake coins is a common problem for collectors. A small exercise of calculating the density of the coin can help. Comparing the density with respect to the known value of the metal will help in establishing the claim. For example, if a coin comes with a claim that it belongs to certain period and is of pure gold. Finding the density of the coin can easily establish or refute the claim as it is very common to make fake gold coins where only the outer surface is of gold and inner core is filled with cheap metal. Remember Archimedes.
Putting the values in the calculator gives 19.3 g/cm3 which is the density of gold. So this coin is of gold.