The Arizona sentinel., 1900-11-14
LA FORTUNA MINE.

In the early days of gold discovery of Califor mia, ls4S, when the news reached the gold miners of Sonora there was general exodus of the able-bodied men who were able to get away northwest to the new Fl Dorado in California aud the state of Sonora contributed many men to the mining population. They took the old road, which was known as the ''camiro real, " frcZn 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 suf- fcient 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 Giia 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 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-lying hills of granite there are big outcrops of rock which to the experienced eye indicate stratif1ed formations. They are indeed strait fled. for the bulk of the range southward and southeastward is composed of regular stratified laminated, hard gneiSsic rock. I use the word ''gneissic'' in a very general and comprehensive sease, for you can describe these rocks with much more accuracy if you localize them as 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 lurium, which by its decomposition 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 levels of the mine. The workings which hGEc. been carried on here have developed g condition of things which could not be foretold from an inspection of the outcrop. The veir or lode appears to be chimney not a contino ous ore body, nor continuous vein with an orC body or chimney or chute upon it. As re marked the outcropping points indicate tha there is no very great longitudinal extension o this ore body.
 The vein is remarkable first in this limited out cc2p; second. in its continuity in depth its con tinued satisfactory richness, and the promise i ,giyes of enrichment bv further veins dipping into it on the foot-wau sides.
 Some facts in regard to the product or yield The ore paid from the surface. The product O. ore extracted up to the .ime has been about g tons per day, which is sent to the 2O-stamp mill each stamp of which crushes about tons il every twenty-four hours. The extraction i chiefly and largely by power drills. A forc' Of 30 men is employed by this mine and mill The greater part of the labor underground anC mining is done by compressed air. The lode was told, was to l5 feet wide This largt space permits the use of power drills to grea advantage. In the material hoisted there ar, fragments of the wall rocks, some of which ar, thrown out but many pieces pass through tht mill. They would prefer to rejec5 most of thi <au rock, b1t it would take more time and ex pease than it does to mill it and there is cha-ce q some as g. a-aja5l.a. gold Eror tsess s5 tons r. roasz -..-.ne5 -siiy -ne averar produc- Is perhaps sls lgo worca 3f gold pc month. Some months they have pro1ucod a high as 3Sa,U9o
 h the region Of the Fortuna mine the lorna tions appear to be wholly of mica slate ant hcrnblende slate with some arenaceous layer Ike old -nicaceouS sands 3ones and quartzites The mine is surrounded by black hornblendi slates and mica Slates dipping southward ant sou hwestward at an angle of about 45 degrees and these states are very evenly lepinated ridge alter r40se. This IS apparently a coA