Mint art. With a clear luster or even mirror background, in places subdued by a stronger patina.
In 1792, after the death of the previous administrator - Efraim Brenna - the Mint Commission decides to put the Mint designation on the coins. Depending on the language used - M.V. (Monetaria Varsoviensis) or M.W. (Warsaw Mint). The present 10 penny is the more popular variety with the letters M.W.
