Antique Sharpening Stone in Custom Coffin Wood Box - PA Estate Find

Very Good shape for age, did not try to remove stone as it's really tight, so I don't know how deep it go's?  This is from old PA Estate, stone has some translucent quality to it, as seen on the edge, stone has a marble type look to it and is super smooth.  See Photos

Overall Size is 11" by 2 1/16" by 2 7/8" high

Stone Top showing is approx. 8" Long by 1 1/8" wide.

Weight of whole piece is 2lbs, 4oz