|Latitude & Longitude (WGS84):||33° 2' 57'' North , 113° 1' 59'' West|
|Latitude & Longitude (decimal):||33.04917,-113.03306|
|Other regions containing this locality:||Sonoran Desert, North America|
|Köppen climate type:||BWh : Hot deserts climate|
A former Cu-Pb-Au-Ag-Mo-V-baryte-fluorspar mine located in secs. 24 & 25, T4S, R8W (Dendora Valley 15 minute topo map), on the western edge of the Painted Rock Mountains and approximately 27 miles west and north of Gila Bend. Started about 1909. Owned by Jack Rowley Fedrick (circa 1952). Discovered 1900. Last produced 1923.
Mineralization is the Rowley vein. The structure is a 4,000-foot fault zone that strikes N30º-37ºW with quartz vein on the footwall and baryte vein on the hanging wall; NE-SW striking shear zone which may represent a fault with Tertiary volcanics to NW and Precambrian schist to SE. Ore control is quartz veins cutting andesite.
Flat-lying Tertiary andesite flows underlie the Jack Rowley claims and the adjoining San Carlos claims. A fault striking 30ºN to 37ºW and dipping 37º to 50ºE. cuts these rocks and extends about 4,000 feet across the claims. Mineralized segments of the fault comprise the Rowley vein, and one segment, about 800 feet long, is exposed on the Rowley claims. The Rowley vein consists of two distinct and adjoining veins in the same fault structure - a quartz vein in the footwall and a barite vein in the hanging wall.
The quartz vein has a fairly uniform width of about 5 feet in the main shaft and on the 125 level for a distance of about 370 feet. The footwall contains no fault gouge or breccia. A few widely spaced tight fractures cut the vein and extend a few feet into the andesite. The vein is massive; nowhere is it brecciated or greatly fractured. There is no gossan or leached zone in or near the vein and no evidence of a zone of enrichment at depth.
Massive quartz and a minor amount of jasper compose most of the vein material, but a small amount of specular hematite and sparse grains of pyrite are present. Some of the quartz is rust-colored from small amounts of hematite and limonite that occur both as inclusions and as stains from weathering of iron minerals in the andesite. Several persistent bands of malachite and chrysocolla, 1 to 2½ inches (2.5 to 6.25 cm) thick, occur within the quartz. These minerals also occur for distances as much as 3 feet along isolated fractures that cut the vein and extend into the andesite. Small pockets of high-grade oxide copper ore and a small amount of chalcocite have been reported.
The barite vein in the hanging wall of the Rowley vein structure ranges from 15 to 30 feet in thickness. Its contact with the quartz vein is sharp and regular, whereas the hanging wall is very irregular. Gouge, 4 inches (10 cm) thick, separates the barite from a 3 to 4-foot zone of fractures and slightly brecciated andesite. Inclusions of andesite are present in the vein within 10 feet of the hanging wall. Barite usually occurs as masses of stringers parallel to the strike of the vein, although some of the stringers are contorted and even bend through an arc of 180º.
Galena is associated with the barite. One pod 5 inches in diameter was seen, and reportedly pods of galena were once mined. Small amounts of calcite are also present.
Molybdenum minerals are present in both the quartz and barite veins near their common contact. Ferrimolybdite forms a thin partial coating on the walls of the main shaft from the surface to a depth of 50 feet. At a greater depth, small stringers containing minute crystals of wulfenite are present in the shaft walls. Some of the stringers cut through the narrow bands of malachite and chrysocolla.
Workings included the main inclined shaft (the No. 1) at 265 feet deep, an inclined shaft (the Jones Shaft), at 125 feet deep, and a vertical shaft 163 feet deep. There are also perhaps as much as 1,850 feet of drifts. The 125 level followed the vein for 370 feet.
NOTE: The Rowley Mine is on private property. Trespassing for collecting, or any other activities, either on the surface or underground, without the permission of the leaseholders, is strictly prohibited.
Commodity ListThis is a list of exploitable or exploited mineral commodities recorded at this locality.
53 valid minerals. 2 (TL) - type locality of valid minerals.
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
|Quaternary - Miocene|
0 - 23.03 Ma
|Cenozoic sedimentary rocks|
Age: Cenozoic (0 - 23.03 Ma)
Lithology: Sedimentary rocks
Reference: Chorlton, L.B. Generalized geology of the world: bedrock domains and major faults in GIS format: a small-scale world geology map with an extended geological attribute database. doi: 10.4095/223767. Geological Survey of Canada, Open File 5529. 
|Pleistocene - Middle Pleistocene|
0.0117 - 0.781 Ma
|Late and middle Pleistocene surficial deposits|
Age: Pleistocene (0.0117 - 0.781 Ma)
Description: Unconsolidated to weakly consolidated alluvial fan, terrace, and basin-floor deposits with moderate to strong soil development. Fan and terrace deposits are primarily poorly sorted, moderately bedded gravel and sand, and basin-floor deposits are primarily sand, silt, and clay. (10-750 ka)
Reference: Horton, J.D., C.A. San Juan, and D.B. Stoeser. The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States. doi: 10.3133/ds1052. U.S. Geological Survey Data Series 1052.