金 Jīn is 'gold':
It's supposed to be a picture of nuggets in the ground.
On the left and a little simplified (except in Traditional Characters), it indicates that the character is something to do with metal:
钱 Qián is 'money':
铁 Tiě is 'iron':
Common word: 地铁 dìtiě 'underground, subway, metro, MRT'