Bonjoy wrote:
I thought it more like the centre of this design at Rowtor http://www.themodernantiquarian.com/post/14393/rowtor_rocks.html , rather than cup and ring.
Yep , it looks a copy .Thomas Eyre (18 th C ) is credited ? with some of the non prehistoric markings , chair etc .

Sorry I don’t understand your ref to Thomas Eyre. Are you suggesting he produced the design at Rowtor (I thought this was accepted as being far older) or are you suggesting he travelled to Ashover to produce a partial copy of the Rowtor marks?