The Arizona sentinel., 1902-02-05
LA FORTUNA MINE.

In the early days of gold discovery Of Califor- mia, 1s48, when She news reached the god minrrS of Sonora, there was a genera. cZUd . .ri Le Able-Oocied men who G'aca a3.e tU E-. away northweS. to the .S I.,l.taJ LI a. i.Jr:li,l and the Stasc Of SUaora cvaoriourei many men to the mi-iing populasi0n. They took ChG o:d road, which was known 1he -c..Iniuo real. 2" from Estancia and Altar northwest ward. nearly parallel to the EGif. following the moan aia ridge known as the Gila range. jlSJ north Of our present boundary. The read led to Yuma. a-ii in passing the Gila range they went wighin d few feet or yards of a very modest outcrup Of quartz which no one seemed to consider Of sui fcient value to merit any attention. That D nm ble and insignificant quartz oG5crOp is today the outcrop of the great Fortuna mine.
 It is situated on the westward sicpe and nc trly at the base of the range of mountains ca.Ied on some of the old maps the Giia range. This trends northwesterly and reaches nearly to the Gila river at the point now known as BlaiSdeu The railway in its course 10 Yuma pasSnS around the northwest point of this range Where the rocks are exposed :t that point they are mostly of homogeneous granite of gray color and weathered out at tna S:-rfaceS which however, are much pitted as if by deconp0.;i- tlon of some soft substance. But beyond these iowlying hills of granite there are big outcropS of rock which to the experienced eya indicate Stratitied formations. They are indeed strait lied. for the bulk of the range Southward and SoutheaStward is composed of regular stratided laIninated, hard gneisSic rock. use the word 'gneiSS1c" in very general and comprehensive sense, for you can describe these rocks with
 
 mica states and hornblendic SlateS. with inter pOlatiOnS 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 presence of some other mineral. possibly, tel luriIm, which b. its decon,DoSition 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 UnrfElnuS VT oh have been carried on here have developed a condition of things which could not be foreSold from an inspection of tho outcrop. The vein or lode appears to be chimney, not a contino- ous ore body, nor Q continuous vein with an ore body or chimney or chute upon i;. 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- tinued satisfactory richness. and the promise it gives of enrichment by further veins dipping into 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 80 tons per day, which is sent to the 2]-Stanp 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 30 men is employed by this mine and mill The greater part of the labor underground and mining IS done by compressed air. The lode, was told, was, to 15 feet wide. This large space permits the use Of power drills to great advantage. In the material hoiS.ed there arc fragments of the wall rocks some of wlich arc thrown out. but many pieces pass thro irh tho mill They would prefer to re iact most of this wall rock. but 1t would take more tine aId ex pense than it does to mill it. and there is g chance of some of it containing god. From these 80 tons of rock crushed daily the average product is perhaps S48000 worth of gold peI month Some months they have produced as high as S9O.00O
 h the region of the Fortuna mine the forma tioaS appear to be wholly Of mica Sla5e and hornoiende slate, with some arenaceoCS layers Ike old micaceouS SandStoneS and quartzitnS The minc is surrounded by black hOrnb!endi. states and mica states, dipping southward ana SouthweStward at an angle Of about l5 degrees and these states are very evenly laminated ridge after ridge.