Page 171 - The Geology and Ore Deposits of Sierra County, New Mexico - Bulletin 10

168 GEOLOGY AND ORE DEPOSITS OF SIERRA CO., N. M.
surface. Water was supplied by one well, which produced 23 gallons per minute with apparently no seasonal variation.
South of the Luxemburg placers the Gold Dust placers, con- sisting of approximately 1,300 acres, are now under lease to the Placer Syndicate Mining Co. This company is also in control of over 500 acres lying just east of the Luxemburg ground, and these entire holdings include ground drained by all creeks which flow off the east slope of the Animas Hills and from Copper Flat. This company has constructed a 4,000,000-gallon reservoir be- tween Dutch and Grayback gulches, and has installed a 5/8-yard portable shovel, a washing and treating machine mounted on a tractor and consisting of a trommel, four 36-inch Ainlay bowls, and a stacker belt, with a capacity of 1,000 cubic yards a day. Records of runs made with this machine, which have been re- ported to the writer, indicate that 1,520 cubic yards removed from the bed of Dutch Gulch just east of where the Animas Con- solidated machine had worked, yielded 67c per yard in gold, and that a later run of 13,388 cubic yards, during which time the machine was out of the richest ground, produced 23.8c per yard, with the gold paid for on the basis of .927 fine and with gold at $20.67 per ounce. The average recovery from approximately 30,000 cubic yards treated was reported to be 39c a yard.
Grayback and Dutch gulches join in the NW.1/4 Sec. 32, and Dutch and Hunkidori gulches join in the NE.1/4 Sec. 33. It is said that surface samples contain fine gold for 3 miles east of this latter point, and nearly all of the land as far east as this and south to the Rio Percha is held as placer ground.
The water supply in this district is a serious problem, as wells to a depth of 85 feet are pumping less than 100 gallons of water per minute, and it is questionable if a large underground supply is available. The water in the Rio Percha is said to be available in part, but its utilization would involve pumping against a 600-foot head for a distance of over 4 miles.
Costs of handling this placer ground are estimated by several engineers who have examined the deposits, to range between 16c and 20c per yard, depending on the cost of supplying water to the machine. The writer believes that with a normal wage scale, and a developed water supply sufficient to keep a machine of 1000-cubic-yards daily capacity in operation, costs will ap- proximate 25c per yard, which will include all operation and capital charges for the plant, but will hardly take care of royalty payments that may be imposed. On the basis of these costs, it seems hardly probable that commercial ground suitable for large- scale operations will be found east of the east line of Sec. 31. Narrow runs along the creek beds and elsewhere in the low areas may be workable as far east as the east line of Sec. 33.
It is reported that in early days $2,060,000 in placer gold was taken from this field, $2,000,000 of it having come from dry operations on the Luxemburg ground. In going over the ground