William R. Watt wrote:

I've never tried putting a metal container in a microwave ...

Ta da!

but its supposed to be noisy and ruin the microwave oven.

Why is it "supposed" to be noisy and ruin the oven?


What do you suppose your microwave oven is made of?

There is one exception which is a metal container with
a special coating for microwaves.

Did you really spend your own money on that? Think about that one for a
moment. Is the "special coating" conductive? Does it absorb microwaves?
Does it reflect them? Is it made of some miracle material that even
Lockheed and the Air Force don't know about yet?

Rick