Proverbs 17:3 The fining pot is for silver, and the furnace for gold: but the LORD trieth the hearts.

Job 28:1 Surely there is a vein for the silver, and a place for gold where they fine it.

Zechariah 13:9 And I will bring the third part through the fire, and will refine them as silver is refined, and will try them as gold is tried: they shall call on my name, and I will hear them: I will say, It is my people: and they shall say, The LORD is my God.