First time around for "Hone ID" help

Picked up this mystery stone with an S.R. Droescher Barber's Gem off the Bay. Smooth on all sides with no visible saw marks. Measures 5-1/2" x 2" x 7/16" and the darker side slurries much like my Thuringians -- medium gray mud.

However, the dark side has some refelective particles which makes me believe this is another type of hone. I have no idea if this is a synthetic or natural stone.

Thanks for the assist, fellas!

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From the size and side shot, it looks like some kind of synth combo barber's hone to me.

That was my best guess, but I'm accustomed to seeing a maker's mark stamped into barber's hones I've seen posted here and on the Bay. When lapping, this sounds very much like the Thuris...it's very hard.

If it's a barber's hone it'll have a sort of ceramic ring to it when tapped. Sounds different than a natural stone. I've got a Celtes hone that has no marking on it, so they do exist without stamps and maker's marks.