The Arizona sentinel., 1901-07-31
LA FORTUNA MINE.

In the early days of gold discovery of Califor- mia, lS4S, when the news reached the gold miners Of sonora, there was a general exodus of the able bodied mon who were able to get away northwest to the new Fl Dorado in California and the state of Sonora contributed many men to the mining population. They took the old road which was known as the ''camino real '" from EStancia and Altar nOrthweStward. nearly parallel to the gulf, following the mountain ridge known as the Gila range, just north of our present boundary. The road led to Yuma and in passing the Gila range they went within a few feet or yards Of very med ,St outcrop Of quartz which no one seemed to consider of sui hcient value to merit any attention. That hum- Dle 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 BlaiSdelI The railway tn it's course to Yuma passes around the northwest point of this range Where the rocks are exposed at that point they are mostly of homogeneous granite, of gray color and weathered out at the surfaces. which however, are much pitted as if by decomposi- ton of some soft substance. But beyond these low-fying hills of granite there are big outcrops of rock which to the experienced cye indicatc stratitied formations. They are indeed strait lied, for the bulk of the range SouthWard and SOutheaStward is composed of regular Stratified lamlnated, hard gneiSSic rock. use the word ''gneiSSic' in a very general and comprehensive sense, for you can describe these rocks with much more accuracy If you locaiiZe them as UllCd SldJeS ana lOFnDlelQlc states. with inter- polations of quartZite beds especially in the upper part of the series, with green stains sun posed to be stains of copper and decompoSi lion of copper ore, which they probably are, al though there are peculiaritieS of color and some yellow colorS. which indicate to me the presence of some other mineral. possibly tel lurium. which by 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 lower levels of the mine. The workings which have been carried on here have developed a condition of things which could not be foretold from an inspection of tho outcrop. The vein or lode appears to be q chimney. not a contino- ouS ore body nor continuous vein with an orc bodY or chimney or chute upon it. As re. marked the outcrorping points indicate that there Is no very great longitudinal extension of this ore body.
 The vein is remarkable first in this limited out crop; second, in its continuity in depth. it's con unued satisfactory richness and the promise il gives Of enrichment by further veins dipping into 1t on the foOt-wan sides.
 Some facts in regard to the product or yield The ore paid from the surface. The product ol ore extracted up to the time has been about & tons per day, which Is sent to the 20Stamp mill each stamp of which crUSheS about tons il every twentyfour hours. Tho extraction i. chiefly and largely by power drills. fOrcr of 80 men is employed by this mine and mill The greater part of the labor underground anC mining IS done by compressed air The lode was told was to 15 feet wide This larg, space permits the use of power drills to grea advantage. In the material hoiSted there ar, fragments of the wall rocks. some Of which ar thrown out, but many pieces pass through tn. mill. They would prefer to reject most of thi wall rock. but 1t would take more time and eX penSe than it does to mill it. and there is chance of some of it containing gold. Fron these 80 tons of rock crushed daily the averag product k perhaps S4S,0O0 worth of gold pc 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 an hornblende slate. with some arenaccouS layer Ike old micaceOuS sandstoneS and quartztes The mine Is surrounded by black hornblendi states and mica states, dipping sOuthward an southwestward at an angle of about i5 degree> and these states are very evenly laminatet ridge after ridge.