In the last few years, experimenting has uncovered the classic Tibetan bell alloys (five, seven and "nine" metals)

Basically, they were just bells shaped like bowls

There is an incredible array of harmonics ranging from the deepest thrum to bright, clear, more bell-like tones

They are modern Nepalese Bell-Bronze, at best, a FIVE metal alloy but likely just "dirty bronze," so I guess they could be called 5-metal, but 7