Casa Grande District
The Casa Grande district includes the Silver Reef and Slate Mountains in southwestern Pinal County. Free gold has been found in veins at the Mammon mine, western Slate Mountains (T. 10 S., R. 4 E.), and probably occurs in other parts of the range. Ellis locates gold placers in the alluvial valley on the east side of the Slate Mountains (T. 10 S., R. 6 E.). No information has been found about the placer gold recovered from this district in 1922.
Literature
Ellis, 1962: Map locates placers in vicinity of Slate Mountains.
Wilson, Cunningham, and Butler, 1934: Describes ores at Mammon mine.
Goldfield District
Small amounts of placer gold have been recovered from deposits in the northwestern part of the Superstition Mountains (T. 1 N., R. 8 E.). The gold was probably derived from free gold in oxidized quartz veins in granite, which were mined at the Morman Stope of the Young mine.
Literature
Wilson, Cunningham, and Butler, 1934: Describes ores in the district.
Mineral Creek District
In 1888, placer gold valued at $400 was recovered from Mineral Creek (Ray district) on the west flank of the Dripping Spring Mountains (T. 3 S., R. 13 E.) in the eastern part of Pinal County.
Literature
Trippel, 1889: Production.
Pioneer (Superior) District
Placer gold was recovered from the southwestern part of the Pioneer district in the vicinity of Picket Post Mountain. The probable source of the gold was eroded material derived from oxidized veins in the area.
