Location
Laguna Mountains north of the Gila River, Tps. 7 and 8 S., Rs. 21 and 22 W.
Topographic Map
Laguna Dam 7 1/2 minute quadrangle.
Geologic Map
Wilson, 1960, Geologic map of Yuma County, Arizona, scale 1:375,000.
Access
From Yuma, about 20 miles east on State Highway 95 to the Laguna Mountains; jeep trails and dirt roads lead to different placers in the mountains.
Extent
Three areas of placer concentration are known on the flanks of the Laguna Mountains. The McPhaul placer area is on the southern margin of the mountains; gravels have been drywashed from the Gila River to about 1 1/4 miles north of McPhaul Bridge (sec. 33, T. 7 S., R. 21 W.; sec. 4, T. 8 S., R. 21 W.). Also owned by H. H. McPhaul is the San Pablo placer claim of 160 acres, probably located in this same area.
The Las Flores placer area is north of the McPhaul placer on the southeast slope of the Laguna Mountains. These small placers are found near the head of an alluvium-floored gulch in the vicinity of the old mines "Golden Queen and India" (abandoned mines located near the border of secs. 26 and 35, T. 7 S., R. 22 W.). Some gold was found in gravels in other gulches on the southern margin of the mountains as far south as the Gila River.
The Laguna Dam placer area is on the east side of the dam on the southwest flank of the Laguna Mountains. Gold was found in gulches draining the mountains, in the bed of the Colorado River, and in potholes in bedrock as high as 100 feet above the river. During the construction of the Laguna Dam in 1907, placer nuggets and a small gold-quartz vein was found at the river margin; part of the placer area was submerged after completion of the dam.
Production History
The placers at Laguna were worked about the time that the placers at Gila City were most active; early production is unknown. Production during the 20th century has been small and intermittent, and production is often grouped with production from the Gila City placers or given under the name "Colorado River placers."
Source
The placers in the three areas of the Laguna Mountains were derived from local gold-quartz veins in the metamorphic bedrock of the area.
Literature
Koschmann and Bergendahl, 1968: History; placer-mining operations in 1884 or 1885; production.
Mining Journal, 1941: Placer-mining operations at San Pablo placer.
Mining Review, 1910a: Notes submerging of placer ground in pothole area at Laguna Dam.
Raymond, 1872: History of placer-mining activity.
