Do you know anything about the etymology of 五金店, or I guess more specifically the compound 五金? A Google search for 五金 on its own makes its meaning fairly clear, but the compound itself is a bit obscure seeming in terms of how it got formed, so I hoped you might shed some light.

(PS Hi, I found your blog via linguaphiles and you're an interesting-seeming guy, so I decided to follow you. Hope you don't mind!)