Proverbs 17:3
The fining pot is for silver, and the furnace for gold: but the LORD tries the hearts.
Torrey's Topical Textbook—AKJV

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.
Torrey's Topical Textbook—AKJV