Coal mine - Oranje Nassau Mines - Heerlen
Salt tower - - Map - World - Hengelo
Table salt - Royal Dutch Salt Industry - Boekelo
Coal - Oil - Hands - Goes
Coal - Coalman - Winter -
Use The Southern Trade Marked Coals - Mining
Lignites - Truax Traer Coal Comp. Velva - Burleigh - Kincaid
