From Age of Titans
Greater Adamanite Armor is the highest and most durable personal armor available in the known world. When battle calls for durability and protection over agility, it is to revered suits of Greater Adamanite Armor that the warriors turn to. Greater Adamanite Armor is generally reserved for the veterans of countless battles and is said that only anti-armor rounds meant for vehicles can hope to pierce the Adamanite shell. Due to the inability to forge new Greater Adamanite Armor's, most armor is now made from existing Greater Adamanite suits, refurbished for battle.
Because of the Greater Adamanite armor's sheer weight and bulk, they're slow-moving and will likely be shot at if foot-slogged across the field,