flint pebbles 1)2-4,4-6,6-8,8-10, ... )bearable 6)competitive pri 1.Product:Pebbles/Man made pebbles/Flint pebbles/Silica pebbles/Cobblestone/Natural pebblesSiO2 99.31%Al2O3 0 ... alk ali proof. We manufacture all sizes and grades of flint pebble(pebbles),natural pebbles(cobblestone),silex blocks(bricks),which are ...