That's pretty much my theory. He snagged the richest and easiest to get to (exposed) ore/specimens and the rest is history. I doubt there's a proper mine per se. If there is, it's probably pretty shallow, thus the reason for no massive tailing piles or well worn trails. I would surmise he probably made a dozen trips in and out and that was it. I find shallow diggings all the time out here in the Bradshaws. Back in the day, a prospector would come across a nice ore pocket, dig it out until it pinched out, then move on to the next one. Thats why the Supers were never all that active. Just not that many exposed veins, or huge placer deposits like there were in many other parts of AZ. I guarantee that area has been thoroughly covered over the years. A lot of people were hungry back in the day.