hi all,urgh:lol: i have been to see a job today its copper honed slate,the customer has bought it already from some internet stone company.had a look and its uncalibrated with a nice flat honed face,the backs leave a lot to be desired ranging from 7mm to 14mm,im starting a honed silver slate job next week as it happens but this stuff is calibrated . bit lost as so what extra to add onto this uncalibrated one and can i expact to acheive a perfectly flat finish with unclaibrated honed slate?