New honing stone, any clue what it is?

[memorael]

Just inherited this and a razor from my granddad wondering if its a coticule or something else. Looks similiar to one but colors are a bit off, I think. This is my first post using photos and had no clue how to do it so Ill just link to the pics in my album... Hopefully. Thanks in Advanced.
http://picasaweb.google.com/rael.ptacnik/Coticule/photo#5196381911456959394
http://picasaweb.google.com/rael.ptacnik/Coticule/photo#5196381920046894002
http://picasaweb.google.com/rael.ptacnik/Coticule/photo#5196381924341861314

[bjrn]

Looks like it could very well be a coticule to me. The dark side looks like slate (and won't hone your razor). I might be wrong on the backing though, if you lap it gives off a brown-purple slurry it'll be a belgian blue.

[heavydutysg135]

That one could be a coticule!

[memorael]

Well, I certainly hope its a coticule. Whatever it is DAMN! i've never achieved such a degree of sharpness before. I don't know if it is the size of the stone, which is pretty small, but maybe this makes it more constant. Not as fast to work with but more constant. Also both sides sharpen but it looks like it wasn't naturally a two sided stone. Anyway my granddad told me its over 80 years old and the brown side is definitely natural stone. So whatever it is, its nice. Finally I can see what the HHT looks like on all the blade not just certain parts.