The usually Basalt stone mosaic size on Sheet:
1)305x305mm ( 12''x12'' )
2)400x400mm ( 16''x16')
3)457x457mm ( 18''x18'' )
4)600x600mm ( 24''x24'' )
5)Thickness: 7mm(0.27''), 10mm(3/8''); 12mm(1/2''); 20mm(3/4'')
6) Standard sizes or as per the customer requested

Chip size: 10x10mm / 15x15mm / 20x20mm /25x25mm /30x30mm.                                                      

The normally shape is square, irregular,  rhombus, round or fanshaped.

Hope our black basalt mosaic tiles can make your contruction beautiful.