3-Plate Method, Surface Plates?

Is it possible that a plate can be lapped flat even though there's chips through-out the surface? A surface gauge would have a big enough base to float over at least some chips, right?
Low spots do not cause problems by themselves, if they are small enough for the test item to bridge the low spots. Also, granite does not get burrs on it sticking up like what can happen to metal surface plates, the granite chips break clean. Dings and other low spots can cause real problems if they fill up with swarf or other junk, but we are supposed to clean the plate and the work well before using it. A bunch of small dings should be no problem at all for a hobby shop, and might be bought for a large discount from 'pretty' plates.
 
I wonder if you could drop them off at the Mt. Airy location and they could send them to Minnesota?
 
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