The Arizona sentinel., 1900-10-17
LA FoRTCSA MINE.


 in tle early days of gold discovery of Califor- mia. 1S4S, when the news reached the gold miners Of Sonora, there was general exodus of the ablebodied men wbb were able to get away northwest to the new Fl Dorado in California. and the sta:e Of Sonora contributed many men to the mining population. They took the old road, which was known as the ''camiro 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 wi hin Q few feet or yards of a very modest outcrop of quartz which no one seemed to consider of suf- 1cient value to merit any attention. That hum be and insignificant quartz outcrop is today the Ou.crop of the great Fortuna mine.
 l. is situated on the westward slope and nearly at the base Of the range of mountains called On some of the old maps the Giia range. This trends rorthweStcrly and reaches nearly to the Gila river at the point now known as Blaisdell. The railway in it's 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 weathcred out at the surfaces. which, however, arc 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 stratifed formations. They arc indeed strait lied, for the bulk of the range Southward and soU- heastward is composed O. regular st-atified lc-nihCted, hard gneissic rock. use the word 'gGeiSSic' in a very general and comprehensive sense, for you ca1 describe these rocks with much more accuracy if you localize them as miJa states and hOrnblendic states, with inter poations of GuartZitc 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 arc, al though there are peculiaTSies of color, and so-,:e yellow cCloTS, which indicate to me the presence of some other mineral, possibly, tel lu-ium, which by its decomposition has given these colors The fact remains, however, that the bullion from the upper part CT the vein COZ tB'1S more copper til3n it now contains in the lower levels of the mine. The workings which have been carried on here have developed a condition of things which eosId nat be f0retold from inspection Of the outcrop. The vein or lode appears to be a chimney not 3 contino- ous ore body, nor continuous vein with an ore body or chimney or chute upon It. AS re- marked the outc-oppinG points indicate tha; th"-e 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- tinied satisfactory richness, and the promise 1t givos of enrichment by further veins dipping inc it on the foct-ETall sides
 Some facss in regard to the product or yield: The orc paid from the surface. The product or ere extracted up to the time has been about 80 tons per day. which is sent to the 2G-stamp mill, each stamp of which crrahes about tons in every twenty-foUr Aours. The extraction is chiefly and largely by power drills. A force e SC n1en is employed 5y this mine and mill. T1l@ greater part Of the labor underground and mining is done by compressed air. The lode I was told. was 10 l5 feet wide This large space permits the use Of power drills to great advantage. In the material hoisted there are fragments q the wall racks some of which are thrown cut, but many pieces pass through the mill They would prefer to reject most of this gal rock, buJ 1t would take more time and ex- panSe than l. does te mill it. and there is Q chance cf some of it containing gold. From tHese go tons O. rock crushed datiy the average p-od'-ct is perhaps S4s O1O worth Of gold per ronth. Scnoe months they have produced as hiGh as S9GOG9
 h the region of the Fortuna mine the forTla- tions appear to be wholly Of mica slate and hornb,ende slate, with some arenaeeous layers E:re old micaceous Sandstcnes and QuaTtzites. The mine is surrounded Dy black hornblendic slates and mica states dipping souUhward and southwestward al an angle of about 5 degrees, and hose eiatos crc very evenly laminatHd, ri.Its alter rlee. This ia aYparc"tfy a cun