Mongolia black Other names: china black basalt, china black Place of origin: china Color: black - tile size 1) 305 x 305 x 10mm /12" x 12" x 3/8" 2) 400 x 400 x 12mm / 16" x 16" x 1/2" 3) 457 x 457 x 12mm /18" x 18" x 1/2" 4) 600 x 600 x 20mm /24" x 24" x 3/4" 5) cut-to-size /customized sizes - slab size 1) small slab: 180-240 x 60/70/80 x 1.7cm 2) big slab: 250up x 150up x 1.7cm - stairs step & riser: 150 x 33 x 3cm & 150 x 15 x2cm 4. Granite quality standard 1) polished degree: ¡ý85 2) thickness tolerance: -2/+1mm qc check pieces by piece strictly before packing. 3) diagonal tolerance: +/-1mm 4) surface flatness tolerance: +/-0.3mm 5) adjacent edge verticality tolerance: +/-0.5mm, precise cutting by infrared-ray-cut machine. Fumigated seaworthy wooden crate for export.