Clairefontaine Crok'Books (10-Pack)

Does anyone know the origin of "Crok" for this style of nb? It seems to be neither fish nor fowl: at nearly B5 size, it may be hard to use as a blank page with neither grid nor line since the Satin finish renders a page a bit too opaque to use the japanese pencil mats I've come to depend upon with Tomoé River paper; but as a sketchbook it seems short on total pages at 24 sheets / 48 pages. And of course the shipping ping is outrageous, adding nearly 90 cents to the unit cost of a single notebook out of the ten. Could anyone speak to their experience using these? Thanks!