Bisbee daily review., 1904-07-23
The Ore Deposits
 occcuRRINe IN the Bisbee District
INSTRUCTIVE PAPER WRITTEN
 sYF. L. RANSoME.
Makes Statement That the Distries Has Produced 400, ,ooo. 900 Pounds of Blister Copper and the End Is No' Yet in Sight.
(By F. L. Ransome, in Mining an
 Co;aptiaa DraSs

(Rv F. l. Ransome. in Mining and
 Scientific Press.)
 The Bisbee quadrangle owes it's economic importance exclusively to the occurrence of ore of copper. The unimportant deposit of lead carbonate in Hendricks gulch, which was the first discovery in the district. Is sun being worked in a small way. and .the Easter Sunday has supplied silceoas gold ore used in the Copper Queen shelter for lining But these, so far as known, are the orly instances in the quadrangle of ores commercial ly exploited for other mentals than copper In comparison with the cop per deposits, the known occurrences of other ores are comparatively in- significant.
 For q district that has produced nearly 400. .000, 900 pounds of copper the Bisbee quadrangle, inspite Of the general baroness of its rocky slopes, exhibits little patent evidence of it's mineral wealth. The porphyry mass of Sacramento hill, and the schists that partially enclose it southeast Of Bisbee, show considerable alteration 11Q tOula pyrite. which by oxidation imparts rusty stain to the rocks. But so far as known no deposits Of value occur wholly within these diScolored rocks. Scne dark rusty masses composed principally of l.monite. outcrop along the Dividend fault in Bisbee. Similar ferruginous lodges occur in Hendricks gulch. on Queen hill and in the lime stones south of Bisbee. Experience has shown that such limonite crop pings, although rarely containing ap- preciable quantities of copper bearing minerals, are nevertheless frequently, although not invariably. associated with an underlying ore body They mark loci of fracturing and minerali- Zation in the limestone. They eyl- dently result from the oxidization of pyrite, the less soluable iron oxide and some silica remaining near the surface, while such copper as was originally present has been carried down by percolating solutions and re- deposited at lower levels. These bodies of limonite. when not too sili- ceous. are the best surface indications of ore that the district affords tldAs Ol tue ulocl POl Adul OA . bodies, on the other hand would have remained undiscovered were superf- cial phenomena alone relied upon to suggest exploration.
 Although the rocks of the quadrangle are scanned with faults and dikes, none of the workable ore deposits occur as lodes or fsssure veins. With a few exceptions they are irregular replace ents of liestone. Originally pyritic, containing probably subordinate amounts of Chalcopyrite, they owe their present value to secondary col- centrations effected by processes of sulDhide enrichment and oxidation.
 The principal bodies of copper ore thus far exploited in the quadrangle are contained with in an irregular area of approximately a quarter of a square mile in extent. This area be- gins on tn enorth in the heart of the town of Bisbee and extends south for three-quarters of a mile. It lies west and northwest of Sacramento hill, anl for the most part between the Czar and Calument & Arizona Urish Mag shafts
 Outside of this limited area no large bodies of copper ore have yet been dis covered. although more or less ore is known to occur in the Lowell, Uncle Sam. Whitehall. Wade Hampton and other mines and prospects. The ex- tent to which future development Ill these outlying properties is likely to increase the known area will be dis cussed in another place.
 rrL large productive mines-the Copper Queen and the Calumet & Arizona In addition to these are few undevelcp- ed mines that have produced com paratively small quantities of ore, and a number of prospects ranging from shallow pits to shafts several hun dred feet deep connected with exten- sive systems of drifts