I came across this site by accident while chasing info on Black American miners in the goldrushes of Victoria, Australia.

Yes, some of our goldfields appear to have been discovered by Black American prospectors, and a paper has been written on this topic. George Boston was listed as discoverer of gold at Boston Gully, the first part of the small St Andrews (Queenstown) rush, and was reportedly later involved in the larger Castlemaine rush. The Ararat goldfield was also first discovered by a Black American, name unknown, at what is now Blackmans Creek. Interestingly, later that year a larger rush on this goldfield resulted from Chinese miners a few miles to the east (the Canton Lead), while walking overland from Robe to Bendigo to avoid the "Head Tax" imposed on Chinese emigrants - they worked it for six months before the European miners found out about it.