Mine would be a 1955 Topps Sandy Koufax RC, which was graded Near Mint by PSA.

Canseco and McGuire rookie card, I grew up watching the A's.. and an old mickey mantle card can't remember the year.

I used to have a Ryan rookie, but I sold my whole collection.

My favorite and probably most valuable baseball card is, 1961 Near Mint, Mickey Mantle.

Two Ripken rookie cards I purchased at the NY State Fair in '90 for about $8 each. Also a '61 Bunning and Drysdale. They don't beat the '62 Koufax!