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That looks like an old Coticule, that could me mined long time ago by any of the Coticule companies that were in business until roughly the second half of the previous century.
It's not possible to determine the layer names of these old Coticules. There were many different mining spots at the old days, that accessed one of 4 existing Coticule deposits, each of them consisting several Coticule layers. Each on of these deposits could be accessed at locations that were often several km apart. And each deposit has it's own layers, with sometimes even different names according to the particular mine. It were the miners that gave the layers names, and they weren't exactly men of science, so there was not something like a layer naming convention. Sometimes they used different names for the same layer, depending on the mining spot. Sometimes they even used the same name for layers of a different deposit. We know the situation for Ardennes Coticule, because they remained in operation, and it also happens to be one of the more documented mining sites. But we can't possibly know the morphology of layers and deposits that haven't been accessed for decades, unless we would find a printed source with proper descriptions. I doubt such a source even exists.
We do have plans however to make a large survey of as much as old Coticules we can lay our hands on, and describe their abrasive properties and appearance. With some luck, that might lead to determination tables for old Coticules. But it will be a lot of work and we haven't even started.