Fireproof Archival Storage. No Ball Cubes.

[steve B]

That does seem like a better option, if only to eliminate the nuisance of removing the plastic.

If it gets hot enough to cause trouble with the mylar I doubt much would survive. If I remember right mylar gets bad around 800.

I saw really mixed stuff about leather and heat. And of course, that was all about regular leather.

If baseballs were cheap enough I might try doing one cubed and one not at fairly high temps for a long time, checking every hour or so. Maybe once flea market season starts back up and I can find them for a buck each or less.