Granite machining in the past

There are a number of granite boxes machined to a remarkably high standard.  This at least means that they were not one offs.

The method I do propose is the use of a bronze blade riding on top of placer emory sand screened to various sizes.  The sand is under pressure and will chew up brittle granite.  The sand may even be glued onto the blade.

Resurfacing every day and then working the surface may well arrive at a perfect inside corner.

My take home though is that placer emory sand does exist and can be separated by sizing and just as obviously recovered as well from cuttings..  With a bronze tool, the emory sand blocks plate damage.

Now imagine a bronze sanding block using fine emory sand.  That inner corner works using craftsmanship alone and plenty ofv time..

Granite machining in the past

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