I was chatting with a couple of folks about terminology for the finish of watch dials, specifically the concentric circles that we see on the registers of many vintage Heuers (as shown below).

It was interesting to see the term "Grailing" used to describe this finish -- ""Grailing" is a cutting process which uses a single-point cutting tool to produce either "a series of fine concentric circles from the circumference to the centre of the work" or "a single fine spiral line, running from the circumference to the centre of the work". Not to be confused with "snailing" of course!!

Have a look here, for descriptions of many additional finishes used in metalworking -- http://www.circuitousroot.com/artifice/machine-shop/surface-finishing/

TAG Heuer seems to call it "azurage", but I am not sure how widespread this may be? Love the term "grailing" in this context!!

John -- any experience from the world of pocket watches? Others -- any thoughts on this lofty topic?

Jeff