The Endumium Ore is an rare mineral block that only generates in Extreme Hills , Swamps and Jungles and drops Endumium Crystals when mined with a Iron or Diamond Pickaxe . It drops 1 Endumium Crystal from each ore block mined and doesn't require smelting (like coal or diamond). The Endumium Crystals are either used to trade with the Farlanders , like the emeralds are used to trade with villagers, or to craft a Block of Endumium .
Previous to the Endumium Crystal, the Farlanders used Ruby as currency. Due to incompatibility with other mods it was replaced with Endumium. Versions prior to v1.1a have rubies.