Sentimentality can make a card valuable as well as scarcity and condition.

The ‘Most Popular Baseball Card Ever’ Is Going to Auction

It is not especially valuable by the standards of old baseball cards (the T206 Honus Wagner has long set that standard), but a vintage “pasteboard” depicting an mustachioed, light-hitting infielder sharing a moment with an adorable puppy named Midget is up for auction. It’s being hailed as the most popular baseball card of all time.