Gold would be so terribly hard to get off the cards - but if you wanted to you would probably at a guess have to put the card in very strong acid to burn off what isn't gold. Even then it would be pretty crap gold. I don't know how old you are but maybe try your Chemestry Teacher or a Chemist.
A Knight is sworn to Honour. His heart knows only Virtue. His blade defends the helpless. His might upholds the Weak. His word speaks only truth. His wrath undoes the Wicked.