Who Wants To Be A FoG Millionaire?

[E.N.]

I was the same as most of the comments Kol copied in, I knew Tin wasn't a "T" but couldn't remember it. Luckily I knew the other three

I think Au is from the Latin Aurus, meaning sun?
Fe like ferrous
Argento is a chain of Irish shops selling silver jewellery that was founded by a mate of my dad