Let the player craft ore Spawners. Ores are spawning randomly in a short intervals and you get 10% more ores from inputed ingots. Ores are spawning only in default:stone so make sure there is one around. This MOD is giving the option of creating lumps back from ingots.
Adds environmental spawners to the map. When enabled, the spawners will be added to newly generated Dungeons and Temples. They are dropping a real mob spawner by change (very small chance).