Placer Gold Deposits of Arizona
Geological Survey Bulletin 1355 (1975)
Table of Contents
Related: Where to Find Gold in Arizona
South flank of the Weaver Mountains. Tps. 9 and 10 N., Rs. 4 and 5 W.
Congress 30-minute quadrangle; Prescott 2-degree sheet, Army Map Service.
Arizona Bureau of Mines, 1958, Geologic map of Yavapai County, scale 1:375,000.
From Prescott, 38 miles southwest on U.S. Highway 89 to light duty road leading 8 miles east to Rich Hill. Dirt roads lead to placer ground.
The Weaver placer area covers about 40 square miles on the south flank of the Weaver Mountains. The most important placer area in production and placer-mining activity is the area at the top of Rich Hill, parts of the sides of the hill, and gravels along Weaver and Antelope Creeks. This district is just north of Octave and east of Stanton (at the intersection of T. 10 N., R. 5 W.; Tps. 9 and 10 N., R. 4 W.).
At the top of Rich Hill, gold was found under boulders and in crevices in the granite bedrock, where it was quickly gathered by prospectors during the early years after the discovery of the placers. Below Rich Hill, in Antelope and Weaver Creeks, the gold was found in reconcentrated stream gravels, a few feet thick to more than 50 feet thick, that contained numerous large holders.
Other placers are found west of this area, in the vicinity of the Planet and Saturn mines (sec. 21, T. 10 N., R. 5 W.). This area probably produced the placer gold attributed to the Martinez district.
The Rich Hill placers were discovered by a party of prospectors led by Captain Pauline Weaver in 1863 or 1864 (one account reports 1862 as the year of discovery) about the same time as the discovery of the Lynx Creek placers. According to many reports, a Mexican in the party found loose gold on the top of Rich Hill while looking for a stray animal. Immense excitement and intense mining activity followed the discovery. Within 3 months, $108,000 in gold ranging in size from a pinhead to large nuggets worth hundreds of dollars was recovered, and within 5 years, $500,000 in placer gold was recovered.
By 1883, about $1 million in placer gold was recovered. The placers have been worked extensively since the discovery, but because of the nature of the gravels, few large-scale operations have been attempted. Most of the mining has been done by drywashers, pans, rockers, and sluices, although some miners used power shovels and dry-separation plants.
There has been no detailed geologic study of the Weaver Mountains, therefore details of the nature of gold-bearing veins are not known. The mountains are composed principally of Precambrian granites and schists that contain numerous gold-bearing veins considered to be of Laramide age. Some of these veins in the vicinity of the placers have been mined for their gold content, and it is probable that the placers were probably derived from these and other similar veins in the vicinity.
Allen, 1922: Location; history; size of gold nuggets; production; distribution of different size particles of gold in different types of placer gravels.
Blake, 1899: Location; size of nuggets; production.
Blandy, 1897: Production estimates.
Burchard, 1882: History; production estimates (1863-81).
1885: History; early placer-mining activity.
Esenwein, 1958: Describes new placer discovery; accessory minerals in placer.
Gardner and Johnson, 1935: Placer-mining operations at Octave in 1931.
Hamilton, 1884: Production estimates; history.
Heikes and Yale, 1913: Area and thickness of placer gravels; size of gold nugget; distribution of gold in gravels; production from 1905 to 1912.
Heineman, 1931: Physical characteristics of nugget from Red Bank placer.
Hodge, 1877: Production from Rich Hill during the first 3 months after discovery.
Koschmann and Bergendahl, 1968: History; production.
Mining Journal, 1938c: Details of placer-mining apparatus at Thunderbird property.
1938e: Describes gravels at Thunderbird placer.
Sawyer, 1932: Detailed description of sampling techniques; includes description of placer gravels.
Watson, 1918: Discusses general history of placer mining at Rich Hill.
Wilson, 1961: Describes placers in Yavapai County (p. 38-57). Location; extent; character of gold; distribution of gold-bearing gravels; placer-mining history and activity.
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