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davidcyclebackA simple start is to examine the team image (not the grey mount part) with a good magnifying glass. If it's made up of a dot pattern, especially a multi color dot pattern, its a modern reprint. If there are no dots, even under high magnification, at least you know it's a photograph. Most modern forgeries or reprints of an item like this will have the dot pattern and was probably made from a computer printer. Forgers sometimes make computer reprints of the photo and pasted to a genuine old mount. So, if it's a common eBay-era reprint, you should have no problem identifying it as such.
If you have a longwave blacklight, the print part will likely fluoresce brightly. Both modern computer and real photo paper usually, though not always, fluoresces this way. Pre-WWII photo paper doesn't fluoresce brightly.
Lastly 19th century photo paper was very thin, much closer to today's computer paper than modern photopaper. If someone pasted a Kodak snapshot on the mount, the thickness alone would be a tell tale sign (plus the Kodak paper would fluoresce under blacklight). I'm only looking at a head-on and one-angled picture so my vision is limited, but the edges look thick, in particular with the chips. 19th century albumen paper tends not to chip like that, as it's so thin and and there's barely an edge to chip.