Oxium

Oxium is a very interesting blue mineral, brought to light for the first time in Martian Dreams.

Description
Holding it in one's possession and then chewing it like bubblegum - though it does have a terrible taste - releases oxygen, allowing the person in question to act in thinner atmospheres as if under Earth-like conditions. Oxium is found on the Mars of the late 19th century, and allows physical activity, unhampered by the thinner martian atmosphere. The Avatar was made aware of its properties by Lt. Dibbs.

However, despite its uses, Oxium is in constant danger of being devoured by the disgusting Oxi-Leeches, for whom Oxium is their favourite food. Even keeping it in a backpack won't save the Oxium from being devoured.

Oxium is also the basic form of currency on Mars. It can be purchased from Calamity Jane at the Trading Post (in either blobs or geodes) in exchange for large amounts of berries, but there is an infinite supply at the Power Plant, as the oxium bin can produce oxium whenever needed.

Trivia

 * An oxium geode can gave 20 - 60 pieces of oxium when being broken apart with a hammer. Since the number is random, saving and reloading can give better results.
 * One should never buy oxium at the Trading Post, since the prices in purple berries are outrageous and the geodes are bogus, only giving one piece of oxium instead of the number above.
 * Though it's most likely coincidential, the cartoon series DuckTales has exactly the same concept with Oxy-Chew.