Yes, Quartz has this problem. Sometimes it is so severe that the surface looks like a Herringbone pattern. The Quartz is variable hardness in spots. The softest spots will over cut and look uneven. The classic solution is to cut with 600 grit, preform with 3k diamond and polish with Cerium. However, nothing is for certain. You may need to experiment. This type of material does need a higher grit preform. No going from 600 or 600/1200 to polish.