Location
Northwest and northeast flanks of the Santa Catalina Mountains, T. 10 S., Rs. 14-16 E.
Topographic Maps
Mammoth and Oracle 15-minute quadrangles.
Geologic Maps
Creasey, 1967, Geologic map and sections of the Mammoth quadrangle, Pinal County, Arizona (pi. 1), scale 1:48,000.
Wilson and Moore, 1959b, Geologic map of Pinal County, Arizona, scale 1:375,000.
Access
From Oracle, dirt roads lead southeast and southwest to the placer areas on both sides of the mountains.
Extent
The Canada del Oro placer area is the large alluvial fan at the northwest end of the Santa Catalina Mountains north and west of Samaniego and Oracle Ridges (T. 10 S., Rs. 14 and 15 E., Oracle quadrangle). Gold is found in gravel beds that reportedly range in thickness from 6 feet at the creek side to 252 feet at the top of the alluvial fan. The gold-bearing gravel occurs over a wide strip along the creek and in adjacent hillsides and extends south into Pima County.
The Southern Belle placer is in creek beds below the Southern Belle mine on the northeast flank of the Santa Catalina Mountains (unsurveyed sees. 19 and 20, T. 10 S., R. 16 E., Mammoth quadrangle). The gold is said to be concentrated in a pay streak on topof red clay material derived from the decomposition of diorite (diabase of Creasey, 1967).
Production History
The placers in Canada del Oro have been known and worked for many years. Some reports state that Spaniards may have worked the gravels in the early 1700's, but I have found no estimates of the gold recovered by these early miners. The deposits have been worked on a small scale throughout most of the 20th century; small amounts of gold were recovered in most years.
Most of the gold occurred as well-rounded particles ranging in size from grains worth a few cents to one-fourth-ounce nuggets. During the early 1930's a nugget worth $25 (at $20.67 per oz) was recovered, and a 16-pound lump containing about 40-percent quartz was said to have been found in the late 1800's.
The placers near the Southern Belle mine were known in 1884 and may have been worked before that time. These deposits have no recorded production and were probably worked out in the early 1900's. Reportedly, the gold recovered was coarse, as some large nuggets were said to have been taken out.
Source
According to Wilson (1961, p. 61-62,) gold-bearing veins in the upper reaches of Canada del Oro, which heads on the north flank of Mount Lemmon, were the probable source of the placer gold in that area. I have found no detailed information about these veins, which were worked at the Copeland, Kerr, Matas, and other prospects.
The gold in the Southern Belle placer is presumably derived from the gold-bearing Southern Belle ore deposit.
Literature
Allen, 1922: Quotes Heikes and Yale (1913).
Blake, 1899: Notes presence of placer gold; source at Southern Belle.
Browne, 1868: Placer-mining activity at Canada del Oro.
Burchard, 1885: Placer-mining activity at Southern Belle.
Burgess, 1903: Locates Southern Belle placer; average gold content in 50-pound sample; describes lode mine.
Creasey, 1967: Describes geology and ore deposits in vicinity of Southern Belle mine (p. 82-83). Does not describe placers.
Heikes and Yale, 1913: Location; thickness of gravels; character and origin of placer gravels; gold values per cubic yard; size of nuggets; production from 1903 to 1912; placer-mining operations.
Hinton, 1878: Notes placer occurrence; profitable workings.
Hodge, 1877: Notes history of mining activity.
Wilson, 1961: History; placer-mining activity during the period 1932-33; origin of gold. Quotes Heikes (1913).
