'Rust' in the Bible

'Treasure not up to yourselves treasures on the earth, where moth and rust disfigure, and where thieves break through and steal,

but treasure up to yourselves treasures in heaven, where neither moth nor rust doth disfigure, and where thieves do not break through nor steal,

your gold and silver have rotted, and the rust of them for a testimony shall be to you, and shall eat your flesh as fire. Ye made treasure in the last days!