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Ardanium was a mineral with the unique property of growing stronger when in presence of radiation. It was used in fuel canisters of big starships, which required huge amounts of power.
A great vein of Ardanium was found on remote planet Questal about 0 ABY or 1 ABY. This led to a great increase of crime, and the notice of the Galactic Empire. Wanting the Ardanium, the Emperor raided Questal to get supplies for a fleet of Super-class Star Destroyers. He imposed Moff Bandor as the ruler of Questal.
However, Bandor was deposed by Rebel Alliance agents including agent codename Tiree, which stopped the Empire from getting more Ardanium.
Ardanium II was a separate chemical with similar properties.
- Classic Adventures: Volume Five