The Arizona sentinel., 1903-01-14

mia, lSiS, when the news reached the gold miners Of Sonora, there a general exodus of the dole-bodled men who were able to get away northwest to the new El Dorado m 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, n 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 a very modest outcrOp of quartz which no one seemed to consider of sui ficient 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 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 weathered out at the surfaces, which, however, are much pitted as if by decompoSi- tion of some soft substance. But beyond these low-lylng hills of granite there are big outcropS of rock which to the experienced eye indicate Stratited formations. They are indeed strait ted, for the bulk of the range Southward and SoutheaStward iS composed of regular Stratitied, laminated. 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 localize them as mica Slates and hornblendic states, with inter pOldtions of quartZite beds, especially in the upper part of the series, with green stains sup posed to be stains of copper and decomposition Of copper ore, which they probably are, al though there are peculiarities of color and some yellow colorS. which indicate to me the prt tSence of some other mineral possibly, tel lul1um which by it's decomposition has given these colorS. The fact remains, however, that the bullion from the upper part of the vein con- talnS more copper than it now contains in he lower levels of the mine. The workings wL .ch hny n hlnr1 rfad IarO condition of things which could not be foretod from an inspection of the outcrop. The vein or lOde'appearS to be chimney. not q contino- ouS ore body nor continuous vein with an orc body or chimney or chute upon it. As re- marked the outcropping 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 it's continuity in depth. it's con- tlnued satisfactory rich eSS and the promise gives of enrichment by further veins dipping nto 1t 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 80 tons per day, which is sent to the 20-Stamp mill each stamp of which crusheS about tons in every twenty-four hours. The extraction is chiefly and largely by power drills. force 0f oO men k employed by this mine and mill. The greater part of the labor underground and mining IS done by compressed air. The lodc I was told, was to 15 feet wide. This large space permits the use of power drills to great ufdntdBe' III tno material nOlSteu there arc Fragments of the wall rocks, some of which are thrown out, but many pieces pass through the mill. They would prefer to reject most of this wall rock. but it would take more time and ex- pense than it does to mill it. and there is chance of some of it containing gold. From these 50 tons of rock crushed daily the average product is perhaps S48,0OO worth of gold per month. Some months they have produced as high as S90OOO
 In the region of the Fortuna mine the forma- tionS appear to be wholly of mica slate and hornblende slate with some arenaceouS layers Ike old micaceOuS SandStoneS and 1'1.. ...,res. The mine is STrrcr1ded oy bIacK nornbendic Sl%.- .-es and mica states, dipping southward and southweStward at an angle of about 45 degrees and these slates are very evenly laminated ridge after ridge.