I will hold my hand up and say that I very very very nearly fell down Pearce's Engine Shaft a few years ago (this has subsequently been properly fenced).
In my opinion, Consols was the apex of Cornish Mining and everything before or since has been a sideshow. DGC is widely regarded as the richest copper lode, but the production from Wheal Virgin from 1757 to 1819 is ignored in the calculations.
If you look at the old sections, there are 2 colours, ground already stoped and stuff the new company did. The amount is phenomenal.
I have asked this question many times and I wonder what lies in the buller/trounson collection. Since the earliest photograph of Cornish mining (that perranporth one at about 1850), it follows that there was a good 20 years of continued massive mining at United/Consols and I for one would be very interested in seeing some pictures of it. The Pool area was snapped to death, but Gwennap seems to have largely escaped it, which is a shame, because it's one of the most interesting areas in Cornwall IMO.