La Veine aux Clous...
They indeed look a bit like La Grise, with wood grain pattern and all, but the color is more neutral gray than La Grise, who usually has either a yellowish or blueish hue. They pattern is also finer.
The only specimen I tested were very soft, "autoslurrying" was more than I ever encountered on any other Coticule. Both hones emerged after part of the aft wall of the quarry came down. I don't think Ardennes bothered to extract the layer under normal circumstances. But since they had to clear the debris of the aft well anyway, I reckon they turned a couple "Veine aux Clous" rocks into whetstones.
Quite frankly, I found them almost useless for real sharpening purposes, at least for the kind of hard steel we're dealing with on razors. They were just too slow. For finishing, on the other hand, they worked just fine, as long as I worked under a running tap. The finish was as good as any Coticule, not better or different in any way. A razor with still good bevel, could be rehoned after dulling on glass, but if you needed to do any real bevel work, they were painfully slow.
When I brought both specimen back to the quarry, I gave my test report to Maurice and he said he wasn't surprised and that he wouldn't sell them for razor use.
On the BBW sides, I can't comment, as I didn't find the time for testing those, back then.
Kind regards,
Bart.