The Arizona sentinel., 1901-08-28
LA FORTTEA MINE.

Zn the early days of gold discovery of Caiifor nia, 1S4S, when the news reached the gold miners of Sonora, there was a general exodus of the able-bodled men 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 tbe old road, which was known GS the ''cuminO 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 cad led to Eu]ns a7l6 in passing the tz3I2 range they went within Few feet CT yards cf v6cE modest UuuCrOp Cf quartz which no one seemed to consider Of sUf- uclent yelGe to merit G-y attention. GhGt hun be and Insignificant quartz Outc-Op is tCacv the outcrop Of the great 37CTy,,.-a .aIue.
 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 in 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 weathercd out at the surfaces which however, are much pitted as if by decomDosi- uon of some soft substance. But beyond these low-lying hills Of granite there are big outcrops Of rock which to the experienced eye indicate Stratlf1ed formations. They ere indeed strait 1Gd- for the bulk of the range Southward and SoutheaStward is composed of regular Stratined laminated hard gneiSsic rock. use the word ''gneissic'' in very general and comprehensive sense, TOT you can describe these rocks with much more accuracy if you locaiize them as mica slates and hornblendic SlateS 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 decompoSition ef 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. pcSSiblv tel lnrium, which by it's decomposition has given these colorS. The fact remains, however that the bullion from the upper part Of the vein con tains more copper than ii 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 the outGrop. The vein Or1ode appears to be a chimney. not a contino- ouS ore body. nor continuous vein with an ore body or chimney or chute upon it. As re- marked the outcropping points indicate that there is no very great longitudinal extension of bhis ore body.
 The vein is remarkable first in this limited out crop; second in its continuity iR depth, it's con tinued satisfactory richness, and the promise it gives of enrichment by further veins dipping iate it on the foOt-wall sides.
 Some facts in regard to the product or yield The ore paid from the surface The product or ore extracted up to the time has been about Si tons per day, which is sent to the 20-Stamp mill each stamp of which c-uSheS shout 1 tons 1T every twenty-four hours. The extraction is chiefly and largely by power drills. 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 6 to b feet wide. This lGrg' space permits the use of power drills to grea duNdnLage- H. bHe uI3Uerlal nOlSJcO IncCe ar fragments of the wall rocks. some of which ar, shrewn out, but many pieces pass through thi mill. They would prefer to reject most of Uni wall rock. but it would take more time and eX penSe than it does to mil it. and there is chance Of some Of it containing gold. FrOn these 80 tons of rock crushed daily the averag product k perhaps Sf8G00 worth of gold pc month. Some months they have produced d high as So0.O00
 In the region of the Fortuna mine the forma tiOnS appear to be wholly Of mica slate an hornblende slate, with some aTenaceoUS layer Ike old miGaceous SandStoneS and qUartziteS The mine is surrounded by black hOrnblendi states and mica states, dipping scUthward an southweStward at an angle of about 45 degree, and these states are very evenly laminateC ridge after ridge.