Metal containers shield plasma ring energies

I put a plasma ring into a metal moon cake container and I stopped feeling its energy. FARADAY CAGE EFFECT!

Faraday cages send electromagnetic signals through them, and prevent them from reaching anything inside them, like say a cellphone or a person. Great for people who don't want to be exposed to 5G.

Anyway, this would be useful for sealing a plasma ring until you want to use it, especially during travel or mass delivery. If only there was a cheap source of small metal boxes...