Some tools were produced in the rough at various sites, or workshops, located at the quarries. Those in Ohio described by Moorehead are probably the most extensive in North America, except the obsidian mines of Hidalgo, Mexico. “The magnitude of the deposit is such,” he says, “that it has given to the locality the distinctive name of Flint Ridge.” It occupies an area about eight miles long by three wide. Here thousands of cubic yards of earth had been removed to reach the flint beneath. “Acre after acre has been so thoroughly excavated that scarcely a single foot of earth and stone retains its original position. Hundreds of wagon loads of spalls cover the ground.” One of the pits formed in this extremely hard stone is almost a hundred feet in diameter and more than eighteen feet deep. The method employed was to build a fire on the rock and then throw cold water on the spot till the edge was broken through and they could knock flakes off of the under side with stone hammers. These were put roughly into shape at some nearby spot and then perhaps taken far away to be finished. This flint formed better tools than that found on the surface.[237] Many of the blades were often piled together for some unknown reason. In sinking a well in a corner of a mound in Illinois, eighteen large flint spades were found a few feet below the surface, closely packed together, and Moorehead found in Ohio the largest “cache” ever brought to light. This formed a mound in the Hopewell group, six feet high and sixty feet in diameter at the base, and contained over seven thousand flint discs about the size of a man’s hand.[238]