Numbers 16:39

16:39 So Eleazar the priest took the bronze censers presented by those who had been burned up, and they were hammered out as a covering for the altar.

Numbers 21:9

21:9 So Moses made a bronze snake and put it on a pole, so that if a snake had bitten someone, when he looked at the bronze snake he lived. ¹ 

Numbers 31:22

31:22 ‘Only the gold, the silver, the bronze, the iron, the tin, and the lead,

[21:9]  ¹ sn The image of the snake was to be a symbol of the curse that the Israelites were experiencing; by lifting the snake up on a pole Moses was indicating that the curse would be drawn away from the people – if they looked to it, which was a sign of faith. This symbol was later stored in the temple, until it became an object of worship and had to be removed (2 Kgs 18:4). Jesus, of course, alluded to it and used it as an illustration of his own mission. He would become the curse, and be lifted up, so that people who looked by faith to him would live (John 3:14). For further material, see D. J. Wiseman, “Flying Serpents,” TynBul 23 (1972): 108-10; and K. R. Joines, “The Bronze Serpent in the Israelite Cult,” JBL 87 (1968): 245-56.