Hamster face isnt much of scientist if he think diamond is a metal. It's also true that many royalty would try extending their life by ingesting mercury, jade, cinnabar, hematite and gold. A good example is the first emperor of the Qin Dynasty emperor Qin Shi Huang who was obsessed with finding the elixir of life in his later years( the guy that was buried with the terracotta army). The tomb contains rivers of mercury and a large assortment of minerals. Another example is the Jiajing emperor who died in 1567 of mercury poisoning from ingesting a large amount of alchemical elixirs.
I knew immortal godmother would take Mu seriously and start gorging on food. Let's see who else follows suit.