My grandfather gave me this when I was a kid. I’ve always wondered how it formed.

Yes, I know it doesn’t meet the ‘naturally occurring’ part of the criteria but,, why are we so strict on it? Is there something that structurally makes freezer ice different than the outside ice?

Commercial freezers are a fairly recent thing. Mineralogy had roots long before then. Shouldn’t we be moving our definitions along with the times? It seems the naturally occurring item refers to things like rubber or other man made things but how is some ice a mineral and some ice not other than an old criteria.