One BGS 10 (Pristine) Leaf Frank Thomas Rookie Card snatched $706 in August of 2017. As one of the more popular Hall of Famers in recent years, it's not surprising that this card fetched a high price. But, it's not a price that you'd expect for a 1990 baseball card that is simply a base card! But, the pose is great and the overall card design is clean and simple. It's very attractive to collectors.
That auction just shows how highly sought after 10's are from collected. Another 9.5 also graded by Beckett only fetched about $110 by PWCC auctions on eBay. It was still well worth getting the card graded. That's no number to sneeze at, but it's no $700! Likewise, a PSA 10 of the same card fetched only $77 by PWCC. Actually, $70 seems to be a fair price for PSA 10 copies of this card, as there are plenty of eBay sales at that price.
At about $20 a card, grading isn't cheap, but it is worth it for this particular 1990 Leaf Frank Thomas card. So, what if you don't want to put the time and money into grading? Well, the great news is that this card is still worth as much as $10 in mint condition! Even better, you can find the entire 1990 Leaf set for $25 or less. That set also has a Sammy Sosa rookie card that collectors are still happy to have.
So, thanks, Frank Thomas, for making the 1990 Leaf baseball set worth collecting!