Step by step instructions for making a precast pebble mosaic (cast inside a frame) . stones are grouted, then backed with concrete - great method for creating custom garden pieces! posted by Ward's Island Community Pebble Mosaic Project:
Insert clay structures into pebbles in a mosaic. This would be super cool in the basement bathroom on the back wall of a shower. Then use plain tile on the facing walls and pebbles on the shower floor.