The Cancer Coin is an essential part of the coin-collecting subquest Signs of the Zodiac and is found in the Weddell Sea inside Iceberg Cavern, coordinates C-3. It's near the waterline marking the the air bubble trapped in the Cavern and is accompanied by a pair of Bald Notothens.
- Cancer is the sign of the Zodiac represented by a crab. Occasionally, this is changed to be a different aquatic crustacean.
- In Greek mythology, Cancer was the crab named Karkinos sent by Hera while Hercules was fighting the Hydra to attempt to harm him and hinder his progress. Hercules crushed the crab and Hera, grateful for Karkinos's effort, placed the crab among the stars.
- In Egyptian mythology, this constellation was represented by a Scarab, a sacred sign of immortality.