The Mining Districts Of Pima County

The valley of the Santa Cruz may be regarded as the cradle of mining in the Southwest. This valley extending far to the north, was the chief route by which the earliest explorers from Mexico reached the then little known northern portion of Sonora, styled "Pimeria Alta." Mines were opened right and left, and the ores were melted in crude but effective adobe furnaces, before the acquisition of the region by the United States in 1853, since known as the "Gadsden Purchase."

Mining then commenced in earnest and United States citizens, especially at the Cerro Colorado and at the Salero and the Santa Ritas, near Tubac, now in Santa Cruz County, also at the Patagonia mine (Santa Cruz County), since better known as the Mowry, it having been extensively worked by Sylvester Mowry. Mining districts were also established at an early date at the Ajo and the Cababi in "Papagueria," the name of the region of Papago settlements, west and south of the Santa Cruz valley.

The position and boundaries of the mineral districts of Pima County are shown upon the accompanying small map, a photographic reduction of the large county map by General Roskruge, upon which the outlines of the district have been drawn by John E. Magee, Esq., for the Chamber of Commerce. The mining records of Pima County show tens of hundreds of entries of locations, many of which have been patented, but many have lapsed and are abandoned. Manifestly it is difficult, if not impossible, to give a complete list or directory of claims, and it is not here attempted, but mention is made of some of the more important and best known claims and mines in the several districts.



The wonderful richness of the copper mines of the Ajo were celebrated throughout northern Mexico before the Gadsden
Purchase and were popularly supposed not to have been included in the sale of the country to the United States. The property was located, according to United States law, by a party of American citizens in 1854 arid was worked by the Arizona Copper Mining and Trading Company. An attempt by Sonorians to take the mines by force was made in 1855 by a company of cavalry from Altar and Ures. Sonora, Mexico, but the soldiers were repulsed. Considerable quantities of native copper  and of rich red oxide (cuprite) ore were sent by teams to Yuma. thence down the Colorado to -the "Gulf, thence to Sari Francisco for shipment to Swansea, Wales; Redeswill Reduction Co. A Boston organization. Seven patented claims and twelve held by location. The properties were formerly held and worked by the late Col. C. C. Bean. Cornelia Copper Co. Two hundred and sixty acres patented.

Adjoins the Oro Blanco District on the north. It includes the Gigas mountains and a part of the San Luis range. Some facts regarding its early history were given in former reports of the geologist, and a brief resume may be permitted. Upon the acquisition of the country under the Gadsden treaty, active exploration of the mineral wealth of Southern Arizona
was commenced by citizens of the United States, and the earliest work was chiefly along the valley of the Santa Cruz and its tributaries, the Sopori and the Sonoita. About the years 1855 and 1857 the best known mineral localities in the Gadsden Purchase were at Arivaca, anciently famous as Aribaca. Sopori, the Arizona mountains, the Santa Rita range, the Cerro Colorado, the Salero, and, further west, the Ajo and the Cababi country. In the year 1856 an association, or company, was formed in Cincinnati, Ohio, for the purpose of sending out a prospecting party to acquire by purchase, or otherwise, one or more of the deserted mining ranches and mines. Col. Chas. D. Poston, of Elizabethtown, Kentucky, with Mr. Herman Ehrenberg and Mr. Frederick Brunckow, engineers, with a party of gentlemen, were fitted out and, after some time spent in visiting the then deserted camps, established the headquarters of the company at Tubac, opposite the Santa Rita mountains and the northern spur of the Arizona or Arizuma mountains, by which name the range is still known in Sonora, just south of the boundary line. Mines at Salero were secured at that time. Several miles northeast of the Arivaca rancho and north of Tubac, in the Cerro Colorado, other and important mining localities were found and acquired, among them being the mines later known as the Heintzelman, the Carlos, Cesario and others. These results led to the permanent organization of the company known as the Sonora Exploring and Mining Company, with Major S. P. Heintzelman, formerly, in 1853, in command at Camp Yuma, as president. Capital was obtained from the eastern states, largely from Colonel Samuel Colt, of Connecticut, the manufacturer of the Colt revolver, and machinery was sent out at great cost for the development of the property. Colonel Poston secured the services of the young metallurgical engineer, Raphael Pumpelly, in addition those of Ehrenberg, Brunckkow and Kustel. For the more complete and satisfactory reduction of the ores, barrel amalgamation by the Frieberg method was introduced. The first bar of silver was produced in 1859. At the breaking out of the civil war the protecting United States troops were withdrawn and it was no longer possible to work the mines in safety by reason of the presence of bands of murderous Indians. The works were closed down. Many tons of valuable silver ore were hidden under the piles of waste and the settlement was abandoned. Messrs. Poston and Pumpelly were the last to leave and made their way almost alone down the Gila to Yuma, and thence across the desert to California and San Francisco. Further notes upon the workings of the Heintzelman and other mines of that region and of Pima County may be found in the report of Professor Blake, the Territorial Geologist, to Governor N. O. Murphy in 1899, pages no to 114. Cerro-Colorado Mining and Milling Co. This historic property, known also as the Heintzelman mine, after a long period of inactivity and neglect, was re-opened in 1908. Area then reported: One patented claim, 71 not patented; five mill sites greatest depth 300 feet. The development work is now in charge of Mr. C. U. Udall, who is sinking a deep shaft. The Liberty Mining and Smelting Co.: The old Liberty and Mary E. group, about 60 miles southwest of Tucson, in the district also known as the Silver Hill about 5 miles south and west of the Cerro Colorado. Nineteen claims, noted for high grade silver-lead ores and considerable shipments.

At the southern end of the range of the same name. It is about 60 miles from Tucson by wagon road which extends northward to Sasabi and El Plomo in Sonora. The ores are mostly native gold and silver.

These two adjoining districts are near the center of the county, about 70 miles west of Tucson by the wagon road. The region was the scene of early historic mining, prospecting and locating. Much work was done there in the decade of the 1880's, and high-grade silver and
gold ore was developed. Picacho "Old Picucho." Noted in the early annals of mining in the southwest for the richness and abundance of its ores of silver which it is stated could he profitably mined and transported far south into Old Mexico for treatment. The great extent of the ore bodies developed near the surface is made evident by the confused network of old shafts, inclines and drifts, mostly caved in and not accessible. Deeper workings in 1909 and 1910 have revealed the existence of ore bodies, which it is believed will rival those of the higher levels, and work is now (in 1910) actively prosecuted.

This district lies southeast of Tucson and centers about the Empire mountains, a short spur of the Santa Rita range. The shipping point is Pantano, about ten miles distant.

Adjoins the Helvetia District on the south, and is chiefly known for its extensive gold placer deposits flanking the Santa Rita mountains on the east side. These placers have been extensively worked and prospected. Accessible by wagon road from Tucson, about fifty miles distant. The nearest railway station is Sonoita, on the Guaymas branch of the Southern Pacific.

The northern end of the Santa Rita range is within the lines of the Helvetia District, which adjoins the Greaterville and the Empire Districts. The shipping point for most of the mines in the Helvetia
is Vails Station, on the main line of the Southern Pacific. The ores of copper predominate. Helvetia Copper Company. Area is estimated by acres (2,500), half patented. Formerly Hughes property. Ores, copper carbonates and yellow sulfide. At and near contact of limestone and granite. Equipped with 150-ton smelter, now idle (1908-1910). Railway to the Santa Cruz projected.

In the western part of Pima
County, near the Ajo District. It includes the Gunsight range, and a portion of the Growler range.

In the northeastern corner of the county, and includes the Santa Catalina mountains. Accessible from Tucson by wagon roads and also from the valley of the San. Pedro.

South and west of Tucson, adjoining Pima District on the west. Thirty miles by wagon road from Tucson and includes the greater part of the Sierrita range.



About 35 miles south of Tucson and adjoins the Sierrita. It is reached by the Twin Buttes branch of the railway from Tucsoci to Calabasas and Nogales. Twin Buttes Mining and Smelting Co. Twenty-seven miles southwest of Tucson in Sierrita mountains. Seven claims patented and 55 not patented. Connected with the Southern Pacific railroad by rail.The four principal claims of the Twin Buttes, are the Senator Morgan, Copper King, Copper Glance and Copper Mill. The ore occurs in well-defined contacts of granite with limestone and in lode-like bodies of garnet, which is the abundant vein-stone. The railway constructed by this company from Tucson, has. with the exception of the branch leading from the valley up to the mines, been disposed of to the Southern Pacific and forms the first portion of the line from Tucson to Calabasas, Nogales and Mexico.

This district lies west of the Cababi District and the Santa Rosa. It became prominent some twenty years ago as a silver producing camp of great promise. It has within its limits gold placers, without water, but worked in a desultory way by the Papago Indians.

About thirty-five miles northwest of Tucson, covering the Silver Bell mountains at the northern prolongation of the Roskruge range, and formerly known as the Abbie Waterman mountains. Imperial Copper Company. About 800 acres patented, twenty-eight claims; balance not patented. E. B. Gage, president; W. F. Staunton, vice-president and general manager. This property is connected with the two smelting furnaces at Sasco, on the Southern Pacific railroad, by the branch known as the Arizona Southern railroad, with a trackage of twenty-one miles. The furnaces have a combined capacity of 750 tons daily. The second furnace was started December 1st, 1908. In five years' time since work at the mines under the Imperial management began, the lodes of copper ore have opened to a depth of 800 feet by both a vertical and an incline shaft.

Tunnels have been cut, roads made, and a town of some 2,000 inhabitants has replaced the solitudes of the desert. Moreover, the smelting town of Sasco, in the valley, has grown up around the furnace plant and is connected with the mines by a standard gauge railway fourteen miles long and with the trunk line of the Southern Pacific at Red Rock. The Imperial carries the names of about 800 men on its pay roll. It mines and ships 600 to 750 tons of ore a day, and Sasco produces 1,250,000 pounds of copper a month. It thus ranks with the large copper producers of Arizona and is growing in extent and importance, with a large area of ground yet to be opened. Mr. Staunton, the general manager, in his report for 1909, says : "The Mammoth mine has continued to be the largest producer during the year both in tonnage and value, the out put having been 89,542 tons. "The occurrence of ore in this mine, as indeed in all our limestone mines, is associated with the contact of the limestone and an intrusive porphyry, the ore bodies sometimes extending for long distances in the limestone, but generally originating at the contacts. The porphyry has broken the limestone into large, irregular blocks, which have been so displaced by fracture and movement as to make the following of the contact (which is the method employed) difficult."

Silver Hill Consolidated Copper Co. The properties of this company are in the Silver Hill mountains, about five miles easterly as the bird flies from the mines of the Imperial Copper Co., and 40 miles from Tucson. The range of elevation known today as the Silverbell mountains was formerly known as far back as 1878 as the "Abbie Waterman mountains." The original mining location in these mountains was known as the Abbie Waterman mine. The property was early extensively worked for lead and silver ore and produced a large quantity of both of these metals. As the work of development proceeded copper ore became the chief product and the mine became known as a copper mine. It is known also as the Paddy Woods mine, and has been extensively developed. The initial properties upon which the Silver Hill Consolidated Copper company was organized, consisted of the five following claims, to-wit: Metallic Beauty, Majestic, Silver Hill, Silver Hill West Extension and Faison. These are patented mines. Subsequent to the organization of the company, it was found advisable by the corporation to cause to be located for it, fifteen additional mining claims. These are admirably situated adjacent to and surrounding the above named five patented mines, and the area enclosed in these additional claims, is exceedingly promising for the production of copper. The copper ores occur in connection with strata of limestone and quartzite at or near the contact of these formations with granite. They are also found in fault fissures following the planes of disruption of large masses of rock

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