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What type stone is this?


jdrichard

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Looks like a hard Arkansas to me. Hard Arkansas stone is a form of Novaculite which is a microcrystaline quartz.

It is an excellent natural whet stone and is used for the final touching up on your gravers (assuming HSS, not sure how it would perform on tungsten).

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I used it to reduce the staff pivot size and it did a great job polishing the pivot. Of course i will not know until i finish the other half and install the balance, hairspring and roller. I may jacot the final staff and use my burnishing tool.


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Looks like a hard Arkansas to me. Hard Arkansas stone is a form of Novaculite which is a microcrystaline quartz.
It is an excellent natural whet stone and is used for the final touching up on your gravers (assuming HSS, not sure how it would perform on tungsten).

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Thats an Arkansas stone. I had a block for tidying screw driver blades and gravers, one like yours for pivot work and a long triangle shape also for pivot work. Just add a spot of oil for best resaults. They will work on tungsten.

Hey, thanks. It does a great job reducing the pivot size.


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