What is "cement city"

Population (2000): 452
Housing Units (2000): 174
Land area (2000): 0.878271 sq. miles (2.274712 sq. km)
Water area (2000): 0.036331 sq. miles (0.094096 sq. km)
Total area (2000): 0.914602 sq. miles (2.368808 sq. km)
FIPS code: 14260
Located within: Michigan (MI), FIPS 26
Location: 42.069269 N, 84.329845 W
ZIP Codes (1990): 49233
Note: some ZIP codes may be omitted esp. for suburbs.
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