A Wheel of the Black March contains and directs the violent energies required for the Circle of Greater Summoning. For Gozeeki to construct a wheel, he will need both large brilliant shards from an enchanter, and dark iron ore from a master miner.
There they are! I hear that dark iron ore is only found in the depths of Blackrock, and I'm sure these shards weren't easy to find either. I am often awed at the dedication you warlocks have. If you instead bent all that energy into the art of bug catching, oh... such a feast you would enjoy!
Sorry, a small digression. I'll create the wheel and keep it for you until you're ready for your ritual.