1.local material 2.polished and natural 3.Nature is the result of nature river pebbles excavation 4.size as ... rate ≤0.2% bulk density 1.85 g/cm3Particle size(mm ) : 2.0 -4.0mm , 3.0 -5.0mm , ... 6.0mm , 4.0 -8.0mm , 6.0 -12.0mm , 8.0 -16.0mm , 12 -20mm , 16 -25mm , 16 -32mm , 30 - ... 40mm , 32 -50mm , 32 -64mm (Other specs. are available) The best selling pebble ...