Other names are Cromcoal and Black Rock.
This was noted in the report. that the intial mentallurgy probes showed any easily accesible, or or mineral wealth.
After Second Crossing
The easy to fine coal ran in seams near the suface, a small one was near Ruatha Hold, to run the system. But more was needed.
Was established for easy to get ore and coal, to replace equipment.. The Minecrafthall is based there.
Second Interval / Third Pass
Late in that interval MasterMiner Birtell, after all the surface seams of coal were gone. So deep shaft mining had to re learned, he sent teams out to find them.