I know pyrite from 24 karat
By saying that he knows pyrite, (which is also known as Fool’s Gold because it resembles gold), from 24 karat gold means that he can tell a real person from a fake one. He can tell real emotion from fake emotion, in the context of the song he might be a fool sometimes but even he can tell when something is real.Its like a girl saying she know a dildo from a real dick. THERE’S A DIFFERENCE!
The picture is a clear example!
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