Proverbs 25:4 Kabbalah

הָג֣וֹ סִיגִ֣ים מִכָּ֑סֶף וַיֵּצֵ֖א לַצֹּרֵ֣ף כֶּֽלִי׃

Take away the dross from the silver, and there cometh forth a vessel for the refiner;