Green hone with orange swirls

I bought this from an antique fair recently. I thought it was a Charnley but not sure as it was caked in old oil. As I lapped the old oil away this beautiful orange swirly pattern appeared. I've not seen one like it before. The only reference I could find to a similar one was on here where Neil Miller has one that could be the same rock. Anyways, it's very smooth but not nearly as hard as a Charnely. I gave it a quick test on razor that had become a little dull and it refreshed it rather well. The slurry smells a little muddy and rusty. The orange is most certainly iron oxide. From Neil's previous post I know it is probably some kind of chert or novaculite. The patterns and relative softness reminds me a little of a Grecian hone I have, although this seems to be considerably finer. Anyone cast any more light on it?



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Looks like a great hone!
Coming back to your qestion on another thread, well it looks indeed a little bit like the ordovician troutstone I described. But the dots and pattern in the ordovician hones are sparse and not eqally distributed over a wide range. The hones are small with different shapes and normally not cut to long benchstones. Your stone looks to have quite a good size. What are the dimensions?

Another thing is that the saxonian oilstones are the hardest stones I have ever had, harder than CF and harder than arkansas. Lapping with sandpaper you do three or four strokes and the paper is dulled and you have to exchange it to have any progress in lapping.

Can you post some pictures of side and backside of the stone?

Thanks for your reply. The stone is actually quite small. The picture is deceptive as it cuts out the top and that is a paddle handle. It's only 19cm by 3.5cm. It is however not as hard as any CF I have seen. It lapped quite easily. So for now at least it remains another mystery green hone (with orange swirl pattern).