... , granite, sandstone, basalt, slate, ect compact structure, texture hard, high compressive strength and water absorption is small, good wear resistance, corrosion resistance ... , Ancient, Tumbled, Sandblasted, Bush hammered, Rough picked (pineapple), ect >>> Quality Control: Polished Degree: 90 degree up; Thickness tolerance: +/- 0.5, +/-1mm ...