When it comes to valuing old baseball cards, there are several key factors that determine the worth. The most important things to consider are the player, the year the card was printed, the condition or grade of the card, and any unique attributes it might possess.

In terms of the player, the bigger the star, the more valuable their cards will be. Iconic Hall of Famers like Babe Ruth, Mickey Mantle, or Willie Mays will almost always command the highest prices. Top players from each era generally hold value best. Even lesser known players can be worth a decent amount if the other key factors line up well.

The year the card was printed plays a huge role. For most sets, the older the card the better. This is because fewer of those early cards tended to survive in good condition compared to more modern print runs. Flagship sets from the early 20th century, like 1909-1911 T206, are extremely valuable as few remain. The 1952 Topps set is also highly valued. Certain late-1980s/early-1990s issues like Topps Traded, Stadium Club, and Bowman achieved cult status and demand has grown exponentially in recent years.

Perhaps the biggest determiner of price points is the card’s condition or grade. Professional grading services like PSA and Beckett essentially “grade” each card on a scale, assessing attributes such as centering, edges, and surface quality for any flaws which detract from a perfect 10. The higher the number out of 10, the better the condition and more valuable a graded card will be. Evententually, some conditioned issues fetch six-figure sums.

Outside of the typical condition grades that services provide, certain unique attributes can increase value significantly. This may include variations like serial numbers, rare airbrushed portraits, error cards, proof issues before the regular set release, and more. Autograph or memorabilia cards that combine a swatch of a player’s jersey with their signature are also highly sought.

Other considerations are the player’s perceived “charm” or story, any records or milestones on the card itself, whether it’s part of a short printed subset, and the overall collectible demand and competition for that player/issue. Scarcity is key – low print runs or a card that wasn’t widely distributed when first released maintain higher value better long-term.

Properly researching all of those aforementioned factors – star power, year, condition/grade, and special attributes – is necessary when accurately appraising old baseball cards. The true worth is best gauged by recently sold prices on the secondary market through platforms like eBay, as conditions and demand can fluctuate greatly over time. By understanding the vital components that drive value, collectors can better determine where their old cards may fit in the current market.