Here you can find a lot of sliced cliffs pieces and few pregathered and cleaned fragments (inner polygons are deleted).
Triangles counts:
SlicedRocks11 - 3252 triangles
SlicedRocks12 - 5380 triangles
SlicedRocks13 - 3976 triangles
SlicedRocks14 - 3146 triangles
SlicedRocks21 - 6430 triangles
SlicedRocks22 - 4740 triangles
SlicedRocks23 - 3844 triangles
SlicedRocks24 - 7608 triangles
SlicedRocks31 - 3206 triangles
SlicedRocks32 - 2804 triangles
SlicedRocks33 - 3212 triangles
SlicedRocks34 - 5404 triangles
SlicedRocks41 - 1986 triangles
SlicedRocks42 - 1760 triangles
SlicedRocks43 - 1366 triangles
SlicedRocks44 - 2000 triangles
SlicedRocks45 - 476 triangles
SlicedRocks46 - 470 triangles
SlicedRocks47 - 162 triangles
SlicedRocks48 - 292 triangles
SlicedRocks4_9 - 272 triangles