Pulling Frank Thomas rookie cards from packs was extra special for me as a kid for one simple reason:

I grew up about two hours southeast of Chicago and would see him play on WGN all the time...

Although I was never a White Sox fan, that proximity made him somewhat more "real" to me than some other stars of the day.

Seeing Thomas launch bombs over the fence on basic cable seemingly on a daily basis quickly made him one of my favorites.

So, I loved nothing more than seeing his cards pop up in those packs of the early 1990s.

And in this guide, I'll take a closer look at each of his rookie cards.

Let's jump right in!

There's one thing about 1975 Topps baseball cards that should immediately jump out at you...

...those unforgettable bright, multi-colored borders.

Some collectors love the design...others hate it.

But what can't be argued is the amount of star power that this set packs.

Key rookie cards of George Brett, Robin Yount, Gary Carter and Jim Rice help headline a set loaded with legends like Hank Aaron, Nolan Ryan, Mike Schmidt and Reggie Jackson to name a few.

And while innovative, those multi-colored borders make this set extremely challenging to assemble in top condition since they are susceptible to showing even the slightest wear.

So, within such an great set, which are the most valuable?

In this guide, I run through the ten most valuable cards to keep your eye on.

Let's jump right in!

Over the years, PSA grading services have brought a critical and much-needed element to this hobby:

third-party opinions on the conditions of sports cards.

Why is that so important?

I can’t tell you how many times I have seen potential deals come and go because I, as a buyer or seller, could not agree with the other party on a card’s condition and therefore its value...

However, when a card is in a PSA holder (or “slab” as they’re often referred) then the confidence of both the buyer and seller increases dramatically.

Basically, PSA acts as the mediator in determining a card’s condition.

And buyers and sellers are usually more likely to transact as a result.

But, while this is the main idea for why PSA grades cards, there are many other reasons to consider using their services.