aggregate of coarse dark grey stones creating a gravel / grit pattern

abstract aggregate backdrop background ballast boulder boulders broken closeup coarse construction cracked crushed crusher dark dirt dust floor fragment fragments geological geology graded granite gravel gray grey grit heap industrial industry irregular light little loose macadam macro material mine mineral monotone natural path pattern pebble pebbles pile piled quarry refracted road rock rocks rough round rubble sandstone seamless shade shades shape shapes shingle size sizes small stack stacked stone stonepit stones stoneware structure structured texture textured wallpaper