Evaluation of continuous grinding tests on some marble and 11 08 2008· A second machine used had one calibrating and five grinding polishing heads for Muğla White Afyon Sky Blue Afyon Sugar marble units and Akköy Beige limestone In the first machine the diameter of each grinding head was 45 cm and rotation rate was 420 rpm Seven abrasive or polish matrixes were fixed onto the grinding and polishing heads