This is a classic, late 1880s cabinet card photograph. The dark hazel cardstock was favoured at this time, as were dark burgundies, and deep forest greens. The photographer's information is printed with gold ink, "Kopke, 405 to 409 Fulton Street, Brooklyn, N.Y."
On the reverse we find an inscription, "Katie from Alfred, July 1888" A negative number is given, #22686, which probably won't help us much since an archive of Kopke's images doesn't seem to exist.
It would have been so easy for Alfred to include last names, but perhaps he was trying for a more familiar tone with his inscription for Katie. Whatever the reason, this decision means that we will likely never know his identity. That is truly a shame.