Description
Gems can be found in the Gems Mine in the Wannies Island. The Wannies mine them, and the Francos extract them into the Zeelichian fuel, called gazogem.
Role in Twinsen's adventure
In order to reach Island CX, Twinsen first had to go to the Island of the Mosquibees. His only way to do this was by calling the ferryman, who is the only link between the islands of the under-gas. The ferryman charged Twinsen four gems for every trip to another island in the under-gas.
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