Millstones were used to grind corn into grits and meal. The late Dr Tom Lumsden explained how the stones were shaped:
At the upper end of Sautee Valley is a small stream known to the early settlers as Mill Rock Branch. Adjacent to it is an exposed
ledge of tough gneiss rock. This formation was known to the pioneers as Stair Step Ledges. From it, they quarried rock used to shape mill stones, which were
extracted by drilling a series of holes in a circular pattern, about four (4) feet in diameter into the rock.
The holes were inclined toward the center at an
angle of about 45 degrees and drilled to a depth of 18 to 21 inches. Into these holes were inserted implements known as gads. Gads were long tapered tools
which when placed in the prepared holes were struck in succession: first this one, then this one, and then the next one, then that one, and the next one.
As this pounding proceeded, the stone would finally give a shiver and break loose from its bed. It would then be placed on a sled, hauled down the road, loaded
onto a wagon and hauled to the mill. At the mill site, special hardened steel hammers, known as mill picks would be used to shape the grooves (lands) and ridges
which formed the working faces of the stone.