Thats a beauty!! I dont know stones that well but from your pics and description i bet it is a wonderful addition to your honing selection!View attachment 937858 View attachment 937859 View attachment 937860 A couple months ago this stone popped up on ebay for a 7 day auction. It was listed as a coticule but it was pretty obvious that it was a primitive translucent (butterscotch at that). I really wanted it but was out bid in the last few seconds. Well, it ends up that my brother bought it and gave it to me for Christmas. Talk about a surprise! It's a killer old trans Ark that's been hammered out on 5 sides and has a 1/4 inch dish on the working surface. I don't think I've ever seen a trans that's dished this badly. Someone really loved this one.
Do keep us abreast of how well it works...