Numbers 16:38-40

38As for the firepans of those who sinned at the cost of their own lives, make them into hammered sheets as plating for the altar, for they presented them before the Lord, and the firepans are holy. They will be a sign to the Israelites.”

39So the priest Eleazar took the bronze firepans that those who were burned had presented, and they were hammered into plating for the altar,

40just as the Lord commanded him through Moses. It was to be a reminder for the Israelites that no unauthorized person outside the lineage of Aaron should approach to offer incense before the Lord and become like Korah and his followers.