Topps 67 Baseball w/ Discolored Backs

[BranchRickey56]

>I put this originally in the wrong Forum, so here it is addressed to the proper audience<

My favorite set has always been the 1967 Topps baseball set. Good photos, great design and it was the first set I started collecting when I became a baseball fan at age 11.

I decided recently to try to put a '67 set together but have been surprised by the number of single cards from this set out there that have discolored or "browned" backs.

Sometimes it will be a strip along one side that's yellowed as if the card had been exposed to light in that area. This seems to make sense if the cards were stored in a box and that little bit of the card had stuck out above the others. But sometimes the entire back will be yellow and washed out.

Other cards are really brown as if they had been exposed to a lot of cigarette smoke. I was thinking that maybe the early card storage sheets had leached chemicals onto the cards or "burned" the cardboard, causing that discoloration. But I don't remember seeing anything like this from when I got out stored my originals in the late 1980s. (My original cards were stolen by the movers during a company paid-for move to Atlanta in 2000- don't ask, it's still a sore point.)

I've bought from both average joe's and reputable dealers on eBay and despite being listed as "NM" or "EX" some still arrive with these color problems.

Anyone have any ideas on this? Are many of the cards from that year like this? My almost complete 1965 Topps baseball set doesn't have any of these kinds of issues and I've been putting it together in the same way. Have I just been unlucky?

Sorry, I can't post scans as I'm having issues with my printer/scanner contraption.

Really just confused and hoping someone can shed some light on this...