Here's a group of dice from the 1940's & 1950's. As you can see, some are 'perfect' (El Morocco, Monte Carlo single, Moulin Rouge), some have a bit of crystallization (Vegas Club, Joe W. Brown's Horseshoe), some are a mess (2 pairs of Monte Carlo, Stateline)!

Both pairs of Monte Carlo and the Stateline have been coated, the others have not. I don't actually know how old the Stateline pair is, but I learned something from them a few minutes ago... it's been several years since I coated them, tonight I noticed they're a bit sticky. They didn't used to be, so now I wonder if they're deteriorating further.

Haven't a clue about lucite...apparently wrapping 'em in paper towels is NOT a good way to preserve them !! Glad you rescued 'em