answers for Patrick (long)
joel
>1) I haven't used them because my regular Norton stones are so good I haven't felt the need to upgrade. both my old personal stones and the multistone we use in the shop.
2) I stock the Black Arkansas because customers request it. Garret Hack (among others) is a big believer in Black verus Translucent. THey are used internchangably but for the same purpose - chasing the wire edge to form the finished edge before stropping.
3) Norton used to not separate out the black arkansas as they mined it because they grade (or used to) by crystal size not by color. It is a special order and is not listed in their catalog. (they don't have a lot of it)
4) Norton's grading in general is tighter than some of their competition (but not all).
5) It is my view that in use there is no practical difference between norton Hard/translucent and Black Arkansas - However some of my customers, and ones that I respect - disagree. In general these same people also think Norton makes a better stone than average. If I was in the market for a stone I would get the black because I always like to think I'll do better with the "best". That being said I have a 11 1/2" x 2 1/2" hard translucent stone that I have set aside from the stock which I will probably use one day - I expect fabulouse results from it but the reason I pulled it was because it is the prettiest sharpening stone I have ever seen with circles of color like an agate.
6) Oilstones got a bad rap in the 70's and 80's when the market was flooded with "consumer" grade translucent stones. I asked at the time (before I was in the busiesses) at Garrett Wade why they didn't carry better Oilstones - (they didn't carry Norton or any of the better oilstone makers) and they said the reason was price.
7) Where it comes in the mine I have no idea. I do know that my own personal Arkansas stone that I have been using for 20 years has streaks of black in it
8) the smooth texture on the stone is due to the way it is finished and not directly proportional to the way it will work.
9) You will be seeing a lot more articles on Oilstone usage in general coming out in the woodworking press.
10) Sharpening stones in general are a specialized market within Norton. I happen to collect sharpening stones, I'm interesting in sharpening in general, and about a year and half ago I was invited up to see the factory and the old Pike Mine where the artificial stones are made. Since I'm highly opininated we get a chance to see and test a lot of new products, some of the products they are introducing I had a hand in helping to design and we sometimes get a chance to introduce a product before it gets into regular distribution (such as their wonderful tack clothes, the boxes for the waterstones, and the new 3X grinding wheels).