Great shortstop and a Hall of Famer. That makes it worth more than a common card. They still are not rare. I was checking ebay completed listings for the past 30 days. There were over 100 cards listed An Aparicio rookie card sold for as little as 99 cents and as much as $865.00. As with any card, the most important factor is condition, condition, condition. The $865.00 card was graded mint PSA9. If you think you have an exceptional card have it professionally graded. Also, in order for a card to have been signed by Aparicio himself, it needs to have two signatures. His rookie card had a facsimile signature, so to be a genuinely autographed card it needs to have a second signature. Even then, signatures can be forged so it would again be best to have a professional appraiser look at it. Hope this helps.