The Arizona sentinel., 1901-10-02
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LA FORTUNA MINE.

DA fORILNA MINE.
 In. the early days of gold discovery of Califor- .nta, ie4S when the news reached the gold miners of Sonora, there WAS a general exodus of the able bodied men who were able to get away northwest to the new Fl Dorado in California and the state Of Sonora contributed many men 10 the mining population. They took the old road. which was known the 'camilo real, '' from EStancia and Altar northHeStward, nearly parallel to the gulf: following the mountain ridge known aS the Glla range, just north Of our present boundary. The road led to Yuma. and in passing the Gila range they went within few feet or yards of a very modest outcrop of quartz which no one seemed to consider of sui 1cfenJ value to merit any attention. That hum ble and insignificant quartz outcrop is today the outcrop Of the great Fortuna mine.
 It is situated on the westward slope and nearly at the base of the range Of mountains called on some of the old maps the Gila range. This trends northwesterly and reaches nearly to the Gila river at the point now known as BlaiSdell. The railway ln its course to Yuma passes around the northwest point of this range Where the rocks are exposed at that point they are mostly Of heterogeneous granite, Of gray color and weathered out at the surfaces which however. are much pitted as if by decoznpoSi- tion Of some soft substance. But beyond these Iow-ylng hllls of granite there are big out crops Of rock which to the experienced ere indicate Strati1ied formations They are indeed strait hed- for the bulk of the range Southward and southeaStward Is composed of regular Stratified laminated, hard gneiSSic rock. use the word ''gneisSicT in very general and comprehensive sense for you can describe these rocks with
 
 mica states and hornblendic states, with inter polationS of QuartZite beds, especially in the upper part of the series with green stains SUD- posed to be stains Of copper and Accommodation of copper ore, which they probably are al- though there are peculElritieS of color, and some yellow colorS, which indicate to me the presence of some other mineral. possibly, tel lurlum, which Dy its decomposition has given these colorS- The fact remains however that the bullion from the upper part of the vein con tains more copper than it now contains in the bn have been carried on here have developed Q condition of things which could not be foretold from an inspection of the outeTop. The vein or lode appears to be a chimney. not continO- GUS ore body nor a continuous vein with an ore body or chimney or chute upon it. As re- marked the outcropping points indicate that this ore body
 The vein is remarkable first ia this limited out crop; second, in its continuity in depth, it's con- tlnued satisfactory richness and the promise il gives of enrichment by further veins dipping into it on the foot-wan sides.
 Some facts in regard to the product or yield The ore paid from the surface. The product oI ore extracted up to the time has been about @ tons per day, which is sent to the 20-Stamp mill each stamp of which cruSheS about 4 tons 1T every twentyfour hours. The extraction is chiefly and largely by power drills. A force Of 80 men is employed by this mine and mill The greater part of the labor underground ana mining IS done by compressed air. The lode, was told, was to l5 feet wide. This large space permits the use of power drills to grea advantage. In the material hoisted there art fragments of the wall rocks, some of which art thrown out, but many pieces pass through tht mill. They would prefer to reject most of thi. wall rock. but it would take more time and eX pense than 1t does to mill 1t. and there is chance of some of it containing gold. Fron these So tons of rock crushed daily the averag, product is perhaps S4S090 worth of gold pe month. Some months they have produced a high as S90-000.
 In the region of the Fortuna mine the forma tions appear to be wholly Of mica slate ant hornblende slate with some arCnaceOuS layer Ike old Inicaceous SandStones and qyartzitcS The mine Is surrounded by black hornblendi states and mica states dipping southward an SouthweStward at an angle Of about 45 degrees and these states arc very evenly laminateC ridge after ridge.