Cast iron bells????

[100model]

I watched this video about a bell foundry in England and they were putting disc brake rotors into the furnace, watch at 2:17 to 2:31. Am I missing something here because bells are always cast from bell metal 80% copper and 20% tin. Does anyone here have an answer as to why they are melting disc brake rotors?



I made a video years ago about making a bell using disc brake rotors, much cheaper than using bell metal.