If by fire of sooty coal the empiric alchymist
Can turn, or holds it possible to turn,
Metals of drossest ore to perfect gold. [ Milton ]

The best metals lose their lustre, unless brightened by use. [ Proverb ]

The finest minds, like the finest metals, dissolve the easiest. [ Pope ]

Shun idleness: it is the rust that attaches itself to the most brilliant metals. [ Voltaire ]

Time is like a river, in which metals and solid substances are sunk, while chaff and straws swim upon the surface. [ Bacon ]

The most civilised are as near to barbarism as the most polished steel to rust. Nations, like metals, have only a superficial brilliancy. [ Rivarol ]

There are two metals, one of which is omnipotent in the cabinet, and the other in the camp - gold and iron. He that knows how to apply them both may indeed attain the highest station. [ Colton ]