'Dross' in the Bible

"Son of man, the house of Israel has become as silver dross to me; all of them [are as] bronze and tin and iron and lead in the midst of a furnace, [even] [as] silver dross, silver [dross] they became!

Therefore thus says the Lord Yahweh: 'Because all of you have become [as] silver dross, therefore look! I [am] gathering you to the midst of Jerusalem,