... abrasives are used for make rough,medium and fine grinding and polishing on granite slabs. They are the traditonal grinding and polishing ... of there traditional abrasives in the grinding and polishing of granite slabs.The relevant grit are as follows:For Rough Grinding ... : 80#,100#,120#,180#, 220#, 240#,280#, 320#,400#For Fine Polishing : 600#, 800#, 1000#,1200#,1500#,1800#, 2000#,2500#,