The Arizona sentinel., 1902-04-09
LA FORTUNA MINE.

In the early days of gold discovery of Califor nia. 1S48, when the news reached the gold miners of Sonora, there was general exodus Of the Sble-bodied men who were able to get away northwest to the new Fl Dorado tn California. and the state of Sonora contributed many men Co the mining population. They took the old road which was known as the ''camino real. from EStEncia 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 tl e went within few feet or yards of very modest outcrop Of quartz which no one seemed to consider of sui hcient value to merit any attention. That hum. ble and insignificant quartz oItcrop is today the oRtcrop of the great Fortuna mine.
 It is situated on the westward slope and nearly st the base of the range of mountains called on some of the old maps the Gila range. This trends northwesterly and reaches nearly 10 the Gfla river at the point now known as BlaiSdeI. The railway in it's course to Yuma passes around the northwest poiat of this ranC6 Where the rocks are exposed at th9. point they are mostly of homogeneous granite. of gray color and weathered out at the surfaces. which how:ver are much pitted as if by decomposi- tion of some soft substance But beyond these low-lying hills of granite there are big cutcropS of rock which to the experienced eye indicate stratified formations. They are indeed strait fed. for the bulk of the range Southward and southeaStward is composed of regular stratified. laminated. hard gneiSsic rock. use the word ''gneiSsic- in q very general and comprehensive sense. for you can describe these rocks with much more accuracy if you locaii e them as mica Si3LcS ana hOfnDlenulc 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 peculi2rities 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 .sf..71 condition of things which could not be foretold from an inspection of the outcrop. The vein CT lode appears to be chimney. not cOntinO- Ous ore body. nor 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, it's con tnued satisfactory richness. and the promise it gives of enrichment by further veins dipping into 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-Stanp mill, each stamp of which crTIShcS about tons in every twenty-four hours. The extraction is chiefly and largely by power drills A force of So men k employed hy this mine and mill. The greater part of the labor underground and mining is done by compressed air The lode. was told. WAS ta l3 feet Wljc. Tbs large space permits the Use of power drills to great advantScr. In the material hOisted there are fragments of the wall rocks. some of which are thrown out, but many pieces pass through ,thf u7ill- They would prefer to reJect most of thEs wall rock. but it would take more time and ex penSe than 1t does tO mtll iJ. and there Is chance of some of it containing gold. From these SC tons of rock crushed daily the average product is perhaps S4S000 worth of gold pcl month Some months they have produced a: high as Sa0.00
 In the region of the Fortuna mine the lorna tionS appear to be wholly of mica slate aHt bornblende slate. with some arenaceouS layer Ike old micaceouS SandStones and quartZibeS The mine iS surrounded by black hornblendi states and mica states, dipping Southward an southwestward at an angle of about 45 degrees and these states are very evenly lamlnateo ridge after ridge.