Today, among various coins of different denominations, there are some rare and interesting pieces of quite unusual shape. Such unusual coins might have high value, being issued in limited edition. Round coins are manufactured easier and they are less likely to wear. Such coins are easy to handle and easy to apply when using vending machines.

Despite the advantages of round coins, various countries decided to issue coins, the shape of which does not suit the general standard. These coins were issued whether for circulation or commemorative purposes.
Read about triangular coins here:
Triangular Coins | Other Coins | articles