Picked this up at an antique store today. Rubbing it with a DMT 325 instantly brings up a rich milky slurry. Surface is very smooth. Used it as polishing stage after a pyramid progression with a Norton 4/8. I'm new to this, and have never actually seen a coticule in person, so would appreciate opinions. Thanks in advance.Attachment 84796Attachment 84797Attachment 84798Attachment 84799Attachment 84800