Going through my 3x5s I found a small stack of "unknowns". Interestingly, I was able to ID a lot of them I couldn't previously, thanks in part to the proliferation of sites like Baseball-Reference.com and the like that weren't readily available "back in the day". That just shows you how long these have been in the closet.
If memory serves, and these days not too well, these came in a collection or accumulation I got in the early 1980s. My best guess is that these are either college football players from the 1960s and 1970s, or possibly NFL players or basketball players. I know most baseball and hockey players by sight from that era, but not football, basketball or the "minor" sports. Likely from that era though.
Even guesses are appreciated. Thanks for looking.