'Smelter' in the Bible

So the craftsman encourages the smelter,And he who smooths metal with the hammer encourages him who beats the anvil,Saying of the soldering, “It is good”;And he fastens it with nails,So that it will not totter.

He will sit as a smelter and purifier of silver, and He will purify the sons of Levi and refine them like gold and silver, so that they may present to the Lord offerings in righteousness.