Slabs - Truly Protective or Harmful?

[drcy]

The major cause of damage to cards is physical handling-- so you if you're taking cards in and out of various holder systems regularly, the physical handling is the biggest potential source.

A serious study of holder, materials etc would be excellent for the hobby, but I think keeping a card in a holder/penny sleeve in dry/dark conditions is good.

As a side note, I got a storage rooms tour of the Chicago History Museum by the head historian, and they have different environmental conditions for different things. Photos are stored in different conditions than say medals. The highlight of the tour was the bed Lincoln died on. It had what they believed were his blood stains, but they weren't willing to do a DNA test yet until it could be done by taking only a very small piece of the cloth (the current required amount of cloth isn't to their liking). Though he said with scientific advancement he assumed it would be done in the near future.

[packs]

The damages you guys mentioned are from the card not being properly secured within the holder, not damage caused by the holder being made of plastic. Before slabs I used pocket pages and smaller cases, they were made of plastic as well.

[steve B]

I've had doubts about the slabs myself.

I believe most are polycarbonate (lexan) which is halfway decent, and has some UV blocking ability.
The sleeves when used are either Mylar - excellent. Or polypropylene, also a fine choice.
While I like SGC for looks, I'm not so sure about the gasket. Acid free is possible but the details aren't known.

The idea I had early on was that for cards on acidic paper like strip cards, and most Topps and Bowman, the slab might seal in the acid from the cardstock degrading. And that would accelerate the process.

I actually asked SGC, and their slabs are not airtight, so there may be enough transfer of air to prevent that.

I do think some study and/or some transparency about materials from the grading companies would be a fine thing.

Steve B

[KMayUSA6060]

I'm surprised, with how much money is thrown around in the hobby, there hasn't been a study on storage materials/slabs. We're in a unique hobby, because each and every one of us is a historian. We are guardians of pieces that tell the history of not only the sport of baseball, but also the United States and sometimes world as a whole. I would think people would want to know more about how to keep these items safe for the long haul.

[TanksAndSpartans]

This thread has some good technical discussion at the end: http://net54baseball.com/showthread.php?t=91156&page=2

[KMayUSA6060]

Originally Posted by TanksAndSpartans

This thread has some good technical discussion at the end: http://net54baseball.com/showthread.php?t=91156&page=2

So based on that, it would seem that all of the slabs are acid-free?

[trdcrdkid]

Believe it or not, this issue -- of cards being potentially damaged by clear materials meant to preserve them -- was being written about by Jefferson Burdick in the early 1940s. The first item below appeared in the October 1, 1941 issue of Card Collectors Bulletin, in which Aywon Exchange discusses the use of cellophane envelopes mounted on album pages to hold cards, and Burdick adds an editor's note recommending instead the use of Crystal Mounts, which were made for blocks of stamps. (I assume Burdick accidentally omitted a "not" when he wrote that they "are said to be injurious to paper and printing".) The second item below appeared in the next issue of CCB, dated December 1, 1941, and in it Burdick warns that ordinary cellophane can damage cards, but that cellulose acetate, which was used to make Crystal Mounts, is safe. The last item, which I previously showed in my post on James Colkitt and the auction of his collection, is from two issues later, the issue of April 1, 1942. It describes how Colkitt was using Crystal Mounts on scrapbook pages to mount his collection of 19th century tobacco cards; Burdick heartily approves, and I suspect that either he told Colkitt about this method, or Colkitt read about it in Burdick's CCB articles and decided to try it.

In any case, the idea of mounting collections of cards in an album, protected by a clear layer of protection, pretty much faded away after the 1940s, though it never totally went away. Plastic sheets made for baseball cards came on the market in the mid-1970s and immediately became very popular, but it turned out that the first generation of plastic pages contained PVC, which could damage cards over periods of many years. I remember around 1980 when this became widely known in the hobby, and everybody was scrambling to get plastic pages with "No PVC".