Probably try to overlay a geological layer onto the sat image...

Probably try to overlay a geological layer onto the sat image and try to find where the Silurian age rocks are hanging out. As you say a 5m wide gossan zone which is 100m in length may or may not be visible depending on vegetation and colour contrast and the quality of satellite imaging, it should appear as an red-orange-brown gossan feature, gossans are sometimes hard to track on satellite and air photo imagery but the blue/green malachite copper is easy to follow once a person is there in the field. The announcement is interesting because the MCT geologists "cherry picked" a few thin zones (thin veins maybe) to deliberately replicate the old Battle Mountain surface rock chip results (which they did), but cautioned that more representative rock chip sampling at surface would show lower Cu grades ( I would guess probably in the region of 0.8% to 1.5% Cu).

Full credit to the MCT geos that they did find these sample locations and also sampled some nearby gossan with more Lead Pb & SIlver Ag dominant mineralisation that the Battle Mountain guys might have missed, this raises the possibility that there might be some sort of Silurian age VHS system out there and these VHS systems can be quite zoned, complex and high grade. Those gossan photos (especially sample locn MTC39146) look like they were very sulfidic, but obviously very oxidized now).

Very early days and quite speculative, but those old timer shafts would have only been after very high grade gold and copper oxides, so they probably would have given up if they were finding Pb or Zn oxides or sulfides as there was no way of treating those sorts of ore back then. I wouldn't be surprised if some of those very old pits and shafts in the photos were actually mined for native silver, as at those sort of grades the native silver might have been quite visible and easy to follow with the naked eye,