These Millstones lay near the Bole Hill quarry. I have always liked the way they were stacked either for storage or for collection I could not tell. Their uniformity suggests a common purpose and that whatever they fitted into was possibly ubiquitous.
Peak District gritstone from which these stones were hewn is perfect for milling, well up to a point. Its big advantages are ease of working, an abundance of raw material, and importantly for the people who used them the stone is self dressing. Dressing a stone means bringing the working edge back to a single plane with no grooves or hollows. This can be done manually with a chisel, but is laboriuos, time consuming and expensive as the wheel is out of production.
Peak gritstone is made up of sandstone sediments interspersed with grains of quartz which is harder. Its is the quartz that does the grinding, but as this wears more gritstone is exposed to the grinding process. This wears down the gritstone exposing more quartz with clean fresh sharp edges, improving the grinding process. This all happens naturally and continuously, which is why they were so in demand.
Most millstones in the Peak were for grain milling with, a few areas provided grindstones for cutlery and blade sharpening. The stones required for the cutlery trade required finer grain structure to prevent kicks in the grinding process. This type of gritstone was sourced further afield from the quarries around Rotherham.
Fashion played a large part in the millstones being left, as though abandoned along the gritstone edges of the Peak. Around 1850 the fashion for white bread started to pick up pace. It was a social statement, if you could afford to eat finely refined white bread, you must be rich, brown bread was for poor people. The only problem for the increase in demand was the millstones. Peak District millstone resulted in grey bread, not appetising. The solution was to bring in French millstones which did not turn the flour grey. Almost overnight, demand for Peak millstones ceased and the unsold stock was just left where it sat, sometimes unfinished, sometimes hardly started.