Found in Atlantia, Molten Ore is a level 40 crafting ingredient that is dropped from the Flame Reaper and Sand Reaper. It crafts the legendary Divine Inferno.
Molten Ore has been confirmed to still be bugged by Rukiryo, even though some players have no problem with it (sometimes it crafts nothing, most probably because it was supposed to craft another sword) . Molten Ore does not craft anything at the moment, and is being fixed.