The Arizona sentinel., 1901-11-20
LA FORTUNA MINE.

Tn the early days Of gold discovery Of Califoc mia, ls4S, when the news reached the gold n1inn'> of Sonora, there was general exodus of s:Je able-bc-died men who we're ai.3 10 cet ayF2S northwest To the new q Dorado iG California 2 and tho state Of Sonora cc2h:lo.,5ed IIla:iy ;Ge5 to the mining population They tooa the O.! road, which was known as the ''camino real from EStancia and Altar northweStward neari, parallel to the gulf following the noIntais ridge known as the Gila range, just north Of ouI present boundary. The road led to Yuma, enc in passing the Gila range they went within 2 few feeto yards Of very modest outcrop Of quartz which 10 one seemed to consider of suf- 1cient 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 GilG river at the point now known as Blaisdell. The railway in its course to Yuma passes around the northwest point of this range. Where the rocks are exposed ct 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 deconpoSi- tion of some soft substance. But beyond these low-iying hills Of granite there are big outc-opS stratiied formations. They are indeed strait fed for the brlk of the range soutnHard ard GoutheaStward is composed Of regular Stratified, laminated- hard gnelSslc rock. use the word ''gneiSSic" iu a very general and comprehensive sense, for you can describe theso rocks with much more accuracy if you localize them aS
 
 polationSrof quartzite beds, especially in the upper part of the series with green stains SUD- posed to be stains of copper and decomposition of copper ore, which they probably are, sl- though there are pecrliarities of color, and some yellow colors, which indicate to ne the presence of some other mineral, possibly, tel luriSm, 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 the lower levels of the mine. The workings which have been carried ou here have developed condition of things which could net be forctoid from an inspection of the outcrop. The vein or lode appears to be 3 chimney, not Q contino- ous ore body nor continuous vein with an ere 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 ou;- crcp; second. in its continuity in depth, its tinued satisfactory richness and the promise it gives of enrichment by further veins dipping tlto 1t on the footrwal sides.
 Some facts in regard to the product or yield: The ore paid from the surface. The product CT ore extracted up to the time has been about 8 tons per day, which is sent to the 2o-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 loGe, l was told. was 6 to Is feet wide. This large space permits the use of power drills to great
 
 fragments Of the wall rocks, some Of which gre 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 eK- pnnse than il does to mill it- and there Is 3 chance Of some of it containing gold. From these 90 touS of rock crushed daily the average product is perhaps S4s000 worth Of gold pei month. Some moathS they have produced as high as SI0,0oo
 In the region ot the Fortuna mine tEe fornla tions appear to be wholly of mica slate anc hornblcnde slate, with some arenaceouS layer Ike old micaceouS sandStoncS and quartziteS The rfre is surrounded by black hornbicndi' states and mica slateS, dipping SouthTard ana southwestwaTIt at cn angle Of about 45 degrees and these states are very evenly laminated ridge after ridge.