Bisbee daily review., 1914-11-01
CALUMET AND ARIZONA MINE AT AJOlS
 ONE OF GREATEST COPPER FIELDS WHICH
 NOW REMAINS LIN DEVELOPED IN ARIZONA
GeOOgst For Company Tells Of Wonderful Deposits And Bright Future Of The AO WCinty-40,O000OO Tons
 Of Copper Ore Is Now In Sight

The following concerning the Ajo district in Arizona. where the Calu.I met & Arizona Mining company has developed 4O,OOO.OO0 tons of copper ore is taken from a paper written by Ira A. Joralemon, geologist for that company. for the Salt Lake meeting of the American Institute of Mining Engineers:
 The Aio copper district lies in south west Arizona. about 30 miles north of the Mexican line, 125 miles wes, of Tucson and 43 miles south of Gila Bend, the nearest ra;:roaC point. The Little Aio Mountains rise a few hun. dred feet above the desert valleys 1 and the camp itself lies in a small basin on the east side of the range. separated from the open desert by | the low hills It's elevation above ssa level is about 1900 feet In the cen. ter of the basin the brilliantly stain. ed rocks of Copper Mountain rise l5O | feet above the village. The scanty supply of water is obtained from the | wells in the desert and from prospect l pits in the camp The nearest abund. ant source of water is the Gna river. i 50 miles north
 Next to Santa Rita. N. M.. the Ato district is said to be the first south. west copper district to be worked by 1 Americans, a high-grade material hay ing been hauled out in the early six ! ties. A good many stock companies ! at one time or another have been ! organized on the strength of surface showings. In the fall of 1911. the Cal umet & Arizona took an option on all ! available stock of the New Cornelta ! Copper company, one of tEe recog- Lized companies that had attempted ! to work the district. The C. & A. started prospecting by diamond drill ing, following this with test biting, and with drifting in the sulphide zone. ! The work resulted in the outlining un- der the iron and copper-stained out crop of a lowgrade copper ore GOV. ering an area of about 55 acres, and reaching a known maximum depth of over 600 feet below the surface. Fol lowing this development, James Phil 1 lips, Utley Wedge and others, under the name of the Ajo Copper company. took an option on the Rendell Ore I Reduction company and the United States Smelling, Refining & Mining l Co.,, took an option on the Chuds T group of claims between the New l CornClia and the Rendeu properties. The United States company gave up it's option after sinking few churn- | drill holes; the Phillips interests, however, still hold their property, but without doing any development work.
 Proving the Ore Body.
 To develop the New CorneIa prop erty. the ground considered as prob ably ore-bearing was co-ordinated with east-west and EoTth-south lines at 1 20O-foot interyals and o-ill holes were sunk at the Intersections; the actual drillins WIS conducted by the F. J. Longyear Co.,. of Minneapolis, and the samrling was done under the direc- tion of the Calumet & Atizona rep resentatives.
 After six months of drilling, test pitting was begun for tho sake of checking the drilling results. The pits were about 4x6 1t in size, sunk |, with windlass and hand drills, MeXl- can and Papago Indian miners being ! employed The work was done on contract, and after practice, the men 1 became so efficient that up to depth of 5 it., test-pitting was cheaper than diamond drilling During the last year of development, test pits were sunk 90 ft deep on the coordinate points in advance of the drilling. in order both to expedite the work and to de- .. crease the drilling cost
 Every tenth bucket hoisted from each hole was taken for a sample and large samples were thus obtained for every round shot Then after the pit was completed, it was resampled in l oft. sections by cutting rectangu- lar vertical groove in. deep by 6 in. wide, SO as to give about a 5OO- 10. sample for each 5-ft section. These channel samples averaged about SIS per cent lower than the bucket sam ples, and were taken for the final sam pies of the pit.
 In the sulphide ore the pits en countered water, which made sinking so slow that only a few hundred feet was done in the sulphide zone. How ever, to check more thoroughly the drilling results i'm the sulphide and prove q constant grade of ore between drill holes. drifts were run on CO., ordinate lines from the bottoms or two of the deepest test pits ana raises were put up from these drifts to check the drill holes. For the sake of giving accurate samples the ma terial broken in each round was hoist ed separately dumped on an iron plate. and every tenth shoyelful talk