Remember gum stains on Topps cards? I'm sure you younger players don't.
I started my collecting career with 1985 Topps. There's nothing special about this Gorman Thomas card, except for the stain on the back. Although my overactive imagination makes me believe that I can detect a faint aroma of 30-year-old gum on the back of this card, the stain is most likely due to wax from the wrapper. It's more than just a stain, there is actually a waxy feel to the stain.
Why did Topps package cards in waxed paper anyway?