The Arizona sentinel., 1903-01-21

nia lS4S. when the news reached the gold miners of Sonora. there was general exodus or the dble-bodied men who were able to get away northwest to the new Fl Dorado ln California, and the state of Sonora contributed many men to the mining population. They LOOK the oio road, which was known as the ''camlno 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 few feet or yards of q 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 northweSteriy and reaches nearly to the Gila river at the point now known as Bla1Sdell.- The railway in its 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, or gray color and weathered out at the surfaces, which, however, are much pitted as If by decompoSl- tion of some soft substance. But beyond these low-lying hills of granite there are big outcropS of rock which to the experienced eye indicate Stratitied formations. They are indeed strait
 fed for the bulk of the range SOuthward and southeaStward is composed of regular Stratifed. 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 locallZe them as mica states and hornblcndic states with inter polationS of QuGrtZite 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 coloTS. which indicate to me the presence of some other mineral possibly, tel lurium, 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 1t now contains in he lower levels of the mine The workings wh .ch have been carried on here have developed Q condition of things which could not be foretod from an inspection of the outcrop. The vein or lode appears to be chimney. not contino- ouS ore body, nor q continuous vein with an ore body or chimney or chute upon 1t. 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, its con tinucd satisfactory rich z cSS, and the promise gives ot 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. A force of so men is employed by this mine and mill. The greater part Of the labor underground and mining is done by compressed air. The lode, I was told, to l5 feet wide. This large space permits the use of power drills to great advantage In the material hOiSted there are 1 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 a chance of some of it containing gold. From these 80 tons of rock crushed daily the average product is perhaps S4S,OO0 worth of gold per month Some months they have produced as high as S90,000
 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 quartziteS. The mine is surrounded by black hornblendic states and mica slltes, dipping southward and SOuthweStward at an angle of about 45 degrees. ridge after ridge.