Location
In the Muggins Mountains, north of the Gila River, Tps. 7 and 8 S., Rs. 19 and 20 W.
Topographic Maps
All 15-minute quadrangles—Wellton, Red Bluff Mountain, Laguna, Fortuna.
Geologic Map
Wilson, 1960, Geologic map of Yuma County, Arizona, scale 1:375,000.
Access
From Yuma, 13 miles east on State Highway 95 to Blaisdell; 7 miles east on light-duty road to Dome. From there, dirt roads lead 10 miles northeast to the Muggins Mountains.
Extent
The only information I have found (other than production data) that describes the placers in the Muggins Mountains is that given by Wilson. The placers are found in the southern and central parts of the Muggins Mountains in the vicinity of Klothos Temple and Vinegaroon Wash.
Placers in the southern part of the range are in Burro Canyon (unlocated) and small canyons in the vicinity of Klothos Temple (sec. 1, T. 8 S., R. 20 W., Laguna quadrangle) and at the southern end of Long Mountain (sec. 7, T. 8 S., R. 19 W., Fortuna quadrangle). The gold-bearing gravels in Burro Canyon occur in ancient bars several feet above the stream channel and in the present stream channel. The gold occurs as particles as much as 0.15 inch in diameter and is concentrated at or near bedrock.
The placers in the central part of the range are near the headward forks of Vinegaroon Wash (which Wilson describes as a long northwestward-trending canyon that bisects the range) in T. 7 S., R. 19 W. (Laguna and Red Bluff Mountain quadrangles).
Production History
The placers in the Muggins Mountains have apparently been known for many years, but they have not been so actively worked as other placers in the same vicinity. They were probably most actively placered during the late 1800's; during the 20th century small-scale placer mining was carried on until 1942.
Source
The placer gravels in Burro Canyon are derived from a Miocene terrestrial conglomerate that contains detrital gold eroded from gold-bearing quartz veins in the crystalline rocks in the range. The minor placers in nearby small canyons and at the southern end of Long Mountain probably have a similar origin.
The gravels in Vinegaroon Wash, which reportedly yielded many rich pockets of gold, are thought to have been derived from erosion of the adjacent metamorphic rocks, which contain gold-bearing veins.
Literature
Wilson, 1933: Location; source.
1961: Location; extent; size and distribution of gold; source; placer-mining activity during the period 1932-33.
