Originally Posted by
Neil Miller
I'm not sure, Dave. As you say, there is a lot of confusion. The only different names used in the past for coticules were 'old rock' belgian hone and belgian yellow stone. In the time I spent in art departments learning screen and intaglio printing, the suppliers catalogues always mentioned german blue and grey polishing stones.
What is for sure is that there is/was extensive quarrying in Regensburg/Bavarian area. Regensburg, BTW, is the same as Ratisbon. Hugh Murray (1779 - 1846) in his Encyclopaedia of Geography mentions many of the rock types from the region and includes gneiss. horneblende, lydian stone, clay-slates, silica-slates, garnet-bearing rocks, slate-whetstones, sandstones, marbles, limestones etc, etc. There is a sample of ratisbon hone in a US museum that has been analysed and found comparable with the belgian coticule. An 1892 volume of The Mechanical News says that the ratisbon razor hone and blue polishing stone may be found as an outcrop in a river bed in the area - Ratisbon is in Bavaria at the joining of the Danube and Regen rivers.
Until it is proven otherwise, I have no especial difficulty in trusting that there was indeed a yellow ratisbon razor hone. Note that the early sources say 'near Ratisbon' so it is probable that Ratisbon was a distribution centre for german-mined products.
Regards,
Neil