His devotion to Ken Griffey Jr., one of baseball’s most beloved ... the average collector might be thrilled to own a handful of rare Griffey cards or even a few hundred unique pieces.

But the rookie card bonanza took off with the 1989 Upper Deck Ken Griffey Jr., a historic card for various reasons. Ken Griffey's Upper Deck card was released the same year as his major league ...

Whether you’re looking to break into the rare or valuable baseball card market or are already a card-flipping enthusiast, here are a few cards you might want to keep an eye on. Ken Griffey Jr ...

Learn More: 15 Things You Can Donate for Money Find Out: 4 Secrets of the Truly Wealthy, According to Dave Ramsey Whether you’re looking to break into the rare ... Ken Griffey Jr. Rookie card ...