Sperry, California

The same ground, surveyed 60 years apart. Drag the handle to wipe between them. Both sheets are United States Geological Survey originals; neither has been altered.

1933 1993

Matched by testing this settlement's coordinate against the published boundary of every sheet in the United States Geological Survey's historical collection. Each opens the scanned sheet at the Survey.

• 1933 USGS Avawatz Mountains quadrangle1:250000, 5 printings
• 1947 USGS Trona quadrangle1:250000
• 1948 USGS Trona quadrangle1:250000
• 1953 USGS Trona quadrangle1:250000
• 1956 USGS Silurian Hills quadrangle1:62500, 3 printings
• 1957 USGS Trona quadrangle1:250000, 5 printings
• 1960 USGS Trona quadrangle1:250000, 2 printings
• 1983 USGS Dumont Dunes quadrangle1:24000, 2 printings
• 1993 USGS Owlshead Mountains quadrangle1:100000

Regional context, not property-specific evidence. The federal mineral resources record lists 4 workings within 5 miles of Sperry: 2 prospects, 2 past producers. None of them still produces. What was taken out: Talc-Soapstone, Nitrogen-Nitrates, Gypsum-Anhydrite. Distance is straight-line from the map coordinates, so a quarry counted here may appear on a neighbouring settlement's page as well.

Every working recorded in San Bernardino County

The eight closest, with where each one stands in the county. Distances are straight-line, computed from the Geographic Names Information System coordinates.

This settlement is recorded in the Geographic Names Information System as feature 252986. The sheet list is computed by point-in-boundary test against the United States Geological Survey's historical topographic inventory. Both are works of the United States government and carry no copyright under 17 U.S.C. 105.

Mines and quarries. USGS Mineral Resources Data System (MRDS) https://mrdata.usgs.gov/mrds/ A work of the United States government, no copyright under 17 U.S.C. 105.