Devonshire Batt, the sandstone scythestone from Blackborough

Dan and I went to see if the Yandles woodworking show was worth Woodwright Designs showing or demonstrating at. On the way back home I decided that we should see if we could find the home of the Devonshire "batt", and so we typed  Blackborough into the satnav. I knew of this stone through some research and had already found a bit of interesting information from the website about the village.
We arrived in this small Devon village and found a very informative display board about the whetstone mining in the area. We also met a gentleman called John who told us more about the industry and pointed out where to look for the mines.

I had better point out that the Devonshire "batt" is a scythe stone. A scythe stone is used to sharpen scythes, which need to be sharpened many times a day. The scythe was used for cutting everything, from grass, wheat, weeds and scrub.

 

To view the image below, just click on it and click again to make it big enough to read. This makes very interesting reading and will tell you everything you need to know. I am just to lazy to type it out.

These are some pictures of the hill, when you walk the footpaths you can see that there is a wide ledge formed around the hill where the miners worked.

In these pictures the mounds are where the miners roughed out the whetstones throwing the discarded materials either side of them.

Dan and I of course had to pick up a couple of likely looking stones to take home and try out. There is a bit of hard chert mixed in with the sandstone which is too hard for sharpening with.

Above is the biggest bit which has been shaped using an angle grinder and belt sander. This stone is 8.5 x 3.5 inches. Below is another smaller stone.

These stones are coarse, and I would only ever use them for rough honing of primary bevels. I only picked up a couple of stones and the grade of them is probably very poor. John told us that there were various grades of stones and the miners would have been selective. He also told us that because of the geology that the largest sized stone was the size of a horses head. This means that only small stones could be made, and large grindstone wheels certainly could not be manufactured.

If you click on the image  you will see the scratch marks this stone left in the bevel of my pocket knife. I would say that the marks left are comparable to a coarse carborundum stone.
I am slowly forming a collection of natural stones, most of which are very hard and fine stones like those from Charnley Forest. These "batts" are certainly on the other end of the scale. I would also be amazed if I was to find a whole "batt" at a sale.
I would now also like to find out if there is anything in the middle of the region of a 1000grit, that was mined in the UK.