Variations in W516-1 set

[marcdelpercio]

I have been collecting and studying all of the cards from the W516 family recently and have noticed a major difference in several of the W516-1's. I know that there are variances in shading/color in this set (and most strip cards in general), however, these appear to have been printed with two completely separate paper stocks and methods.

One variation has a bright white, thicker, multi-layered, almost glossy paper stock. Notice the chipping around the border of the Burns card below.

The other version is printed on a thinner, single-layered, tan colored paper stock.

All cards seem to appear in both versions and are otherwise identical. I have searched past threads and have not been able to find any other mention or discussion of this. Just wondering if anybody else has noticed or catalogued this or if anybody would even consider this to be a difference worth noting.