The Left half is Combined with the Moonstone (Right half) to create the Blue Moonstone. It is found during chapter 3-2 in the Courtyard. The pieces do not need to be found in Easy mode as the door it unlocks is already open.
- Koichi Hamamura, ed (2006) (in Japanese). biohazard4 kaitaishinsho revised edition. Famitsu. ISBN 4-7577-2638-4.