What is "mineral hills"

Population (2000): 214
Housing Units (2000): 95
Land area (2000): 1.449727 sq. miles (3.754776 sq. km)
Water area (2000): 0.000000 sq. miles (0.000000 sq. km)
Total area (2000): 1.449727 sq. miles (3.754776 sq. km)
FIPS code: 54580
Located within: Michigan (MI), FIPS 26
Location: 46.116338 N, 88.647411 W
ZIP Codes (1990):
Note: some ZIP codes may be omitted esp. for suburbs.
Headwords: