Mexican COIN ART 50 Centavo's coin Silver metal

I am calling this, COIN ART, a term I heard used in the past for this type of item. Also I have been told that Apprentice Jewellers where given the task of cutting the excess metal from a coin design as a final test of their skills, don't hold me to either of these theorys. A Silver, Mexican 50 Centavo Coin, 30mm across, in which the metal has been cut away form the letters and the Bird holding Snake centre. Pin back fastener added. Very fine detailed work by a Very Skilled jeweller.

Control #WS4403