This worked well as the dirt was soft fill dirt. BUT when we came to the back corner where John had poured cement over the raised mound, it was the original hillside clay and chalkrock! A hard swing of the pick would remove only a SMALL chunk! H ere we are looking at the back corner behind Devil's Gulch where the big mirror was. Scalp is gone, and we have dug to about the bottome of Devil's Gulch.