I've posted the walnut burl as grade 1,2 or 3 or something like that. In my case the grading is.
1. at least some knowledge of what sort of grain would be preferable in a pen. This would not be true from the run of the mill wood seller. They are not being dishonest but grade 1 wood for a table top is not grade 1 wood for a pen.
2. a comparison of one blank to any other blanks from this same lot of wood.
so grade 1 in my case is the best of the best I have while grade three is the worst, or pieces with the least figure in the grain etc.
Finally in the real world of wood grades are specific and definable. it has more to do with moisture content, clarity of the grain and finishing of the lumber. an example is finish grade lumber or also known as clear lumber does not have any loose knots, checks, splits or other imperfections. none of this would be relative to pen blank or the grading of them. other lumber grades would be something like CDex plywood which means one side of the sheet is grade C while the other is D the (ex) means it is rated for Exterior use. Just keep in mind that any decorative wood will be graded with an end use in mind. I have wood that will make killer peppermills but would be nearly useless for pen blanks.