As I know little about honing stones and the quarries these came from I have attached lots of photos to help and hopefully they will give you experts an idea of what stone this is, the face is like glass does have some scratch marks it looks to be a blue/green/grey colouring, the bottom part is very roughly cut as is the stones length, the box has been made to fit the angle of the end of the stone, measures 8” x 3” x 1”. Hopefully one of you may know the quarry that this came from. An absolute beautiful stone and think once cleaned and lapped would grace any stone collectors collection, I know the stone has some age to it as I bought some early made woodworking tools from the same person. 

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