|Release date||1 August 2005 (Update)|
|High Alch||36 coins|
|Low Alch||24 coins|
|Store price||Not sold|
|Exchange price||11,871 coins (info)|
|A spherical chunk of rock-shell.|
Giant rock crabs are found in the Waterbirth Island Dungeon, while King Sand Crabs are located within the south-eastern section of the Catacombs of Kourend. Players may find King Sand Crabs more favourable to kill for rock-shell parts, due to the lower melee defence; it should be noted, however, that Giant Rock Crabs have a -10 Magic defence bonus, which makes magic more effective on them.