I do not know if you are still looking for information, but my nephew says his ggggfather was
William Carl Schwarz, b Feb 13,1846, d Mar 15,1931
also that he came from Schartovswalde, Bradenburg, Germany

This is all the info they have on him. Do you have any more info now? I will pass on your post info to see if any of that is a match.

Thanks,
Brian