Twenty pence coin with an extra piece of silver on Queens head is this classed as faulty?

Answer 1

Any coin with a "genuine" minting flaw would have some value, above the usual, as a collectible coin. Genuinely flawed coins are not necessarily known about or documented until somebody turns up with one, since they are an "accident" of the minting process, and have escaped detection during quality control at the mint therefore, a valuation cannot be anticipated. A reputable coin dealer should be able to identify and confirm the coin as genuine and make a valuation. Flaws and errors on coins should not be confused with mutilation or mangling of the coin. It should be noted that many people have the interest, skill and enthusiasm to fraudulently alter otherwise normal coins for the purpose of personal gain or notoriety. Also, many coins are commercially produced for magic or trick purposes and these include "double headers/tails" and "impossible" coins like a US silver Dollar on one side and a British copper Penny on the other.