The rarest Russian coin is Constantine silver ruble. Russia has never had Emperor Constantine but it has his coin. The fact that this coin exists prove the dynastic crisis in Russia after death of Alexander 1st. He had no son and the throne was inherited by his brother. As he had three of them the elder was crown prince. The Constantine was.

As soon as Alexander 1st joined to majority the minister of finance Kankrin ordered to mint the coin with the portrait of new Emperor expecting Constantine would be. After …