Last night I decided to autoclave (sterilization process that uses 125 C steam) the tin container that Altoids mints come in in order to see if they would survive the temperature/pressure. The tins looked the exact same inside and outside after autoclaving.
It is not a huge surprize the tins survived – they are metal after all. My actual intent in doing this was to use the tins as petri-dishes – which is why I needed to sterilize them in an autoclave. But while the autoclaving of the tins went flawlessly, my media preparation failed miserably. I tried to make some growth media with red wine, body-builder amino-acid supplements, sugar, and agar-agar (edit: FYI I boiled off most of the alcohol). For whatever reason the media would not harden. I will try again sometime after this week because I will be going to the TAM conference in Vegas this year!
As far as using these containers as petri-dishes goes – my only concern is the hinge. It appears that when closed, the lid covers the hinge hole and should keep the innards sterile. Until I get the media to harden I will not know if that is a problem or not.
Even if the tins fail to work as petri-dishes (metal could have unforeseen issues for micro-organisms), they may work out as containers for auto-claving parts or components.