Thread: what hone is this?

My educated guess is Dronfield Slate

Originally Posted by Iceni

What dimensions is it.

I have a stone of very similar, very dark almost black colour. It's also a UK stone. Came in an unbranded card sleeve.

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Mines 2x8 inches and 1/2 thick.

It can work as a finisher, but it's under an 8K naniwa finish. I suspect it to be something like a cambrock silkstone. It's at it's most basic description a med hard slate. Slurries well with a diamond plate, but doesn't auto slurry. Suffers with serious slurry dulling on a heavy slurry.

here some closer pics, it seems to me very low grit.

I agree, those crater marks definitely look like a very low grit stone

Or badly, in need of lapping, depends on the price, I have certainly bought a boat load of black stones at garage sales and flea markets for a buck or two, and have ended up with a few clunkers, but also a lot of gems.

But generally if someone made a box or paddle for it, that is a good sign.

Depends on the price, may be worth a chance. For hard stones, lap with loose grit Silicone Oxide, soft stones a 140 grit diamond plate.

Originally Posted by Euclid440

Or badly, in need of lapping, depends on the price, I have certainly bought a boat load of black stones at garage sales and flea markets for a buck or two, and have ended up with a few clunkers, but also a lot of gems.

But generally if someone made a box or paddle for it, that is a good sign.

Depends on the price, may be worth a chance. For hard stones, lap with loose grit Silicone Oxide, soft stones a 140 grit diamond plate.

yes but even after lapping fine, it won"t be go above 10k.

Yes, but you won’t know until you lap it. And it does not have to be 10k to finish. Very few natural stones are over 8k and still finish very fine.

As I said, depends on the price, for a dollar or two I would take a chance, more, you will have to decide.

With high grit natural finishers it is not just about the grit size, the kind of grit, the frangibility of the grit and binder and or the hardness of the stone all play a part in the finish it produces, oh yea… and the driver.