Schuyler,
  There is a town about 20 miles from me that used to have two cement
plants - Superior Cement and Washington Portland Cement and the
town is called "Concrete".  Actually it's a little more interesting than that
the town on the West side of the Baker River was called "Cement City".
Then they built the Superior cement plant in Baker on the East side of
the river - and when that was built they merged Cement City and Baker
into the town of "Concrete" (County of Skagit, State of Washington).
  Yes, you're correct in your terminology - but common use substitutes
Concrete for cement in many mouths - and vice versa ... and even a
small primarily two plant town calls itself Concrete when what they
make is cement.  The two cement plants were almost entirely built of
concrete and the schools in town were also of concrete construction
(as were other major buildings such as the Library).

  Concrete will be a significant town on the layout I'm building - perhaps
I should call it "Cement City" since I'm not going to do the entire town?
(Yes, there was also a lumber mill in Concrete.)
  I'll be hauling concrete in both early covered hoppers and box cars.
But any concrete being hauled around Concrete will be in - wait for it -
cement trucks.  ;-)
                                                                                                      - Jim