Why were they abandoned?
The millstone industry in the Peak District had been hugely successful for hundreds of years; there is reference to a millstone quarry at Alderwasley, on the edge of what is now the Peak District National Park, as far back as 1257. Right up until the 18th Century millstones made from millstone grit were in great demand and business was brisk.
Then, two things changed.
Firstly, at the start of the 18th Century white bread became more and more popular, which required finer, whiter flour. Unfortunately, the millstones made of Peak District gritstone often left tiny fragments of stone powder in the flour, which made it undesirable for use in a finer, whiter product. To address this issue, composite millstones made up of separate blocks of chert (a type of quartz) were introduced, and the Peak District stones suddenly had significant competitors.
Secondly, in the late 19th Century machines became more commonplace in the mills. They allowed high speed grinding and thus subjected the millstones to more wear. The millstones made from Peak District gritstone wore down quickly and required re-cutting regularly. Again, the chert composite stones proved to be far superior.
The chert composite stones are often referred to as ‘French stones’, although they were actually made throughout England as well as in France. It’s also sometimes claimed that they were cheaper than gritstone millstones, whereas actually they were more expensive; it’s just that they lasted longer and required much less maintenance.
The introduction of these composite stones sounded the death knell for the Peak District millstone. In many areas the industry died out very swiftly; so quickly that the half-finished stones were simply left in their incomplete state on the moors, or abandoned where they lay awaiting transport to their destinations.