The Arizona sentinel., 1901-04-24
c, P. GROWN. County Recorder.
TERRITORY OF ARIZONA, lss
CASTLE DOME DISTRICT.

The veins of the Castle Dome district may be said to have been rcdiscovered in IS63 for it was evident that they had been ancently worked, iss already stated in the historical introduction. The metal had been taken out from many of the veins by the ancient miners down to a depth of from to I5 feet and in continuous lines of trenches in some places for 50 to leo feet or more. These old workings were found to be safe guides to good metal bearing ground q short distance deeper. Well worn trails leading of from these pits to the banks of the Gila river some IS miles distant. and the ruins there of some rude sneiting furnaces, indicate that the ores were carried to the Cila, probably On the backs of Indians and that they were smeltcd there, whether by the AztecS or the caTiy-arriying Spanish explorer is not known. Since 1863 these mines have been worked almost continuously and are now yielding Silver-lead ore of most excellent quality which is shipped to San Francisco. The claims were worked by the prospecrors without capital until October, 1870. Up to January l. 1892 there had not been an investment of over S30O in building or pcI- malent improvements. The climate is such that men can work the year round without no more protection than is afforded by brush, hutS or tents.
 The veins crop out on a rolling plain or mesa at the base of the Castle Dome range. a very rugged and picturesque group of mountains trcnding northwest and southeast. rising near the center to the remarkable dome-shaped sum- nit with prccipitous sides. looking like a huge round castle or building with dome. It is noted landmark, being visible from a great dis tance in all directions. It was originally called Capitol Dome" by the officers at Fort Yuma in 1853, from the fancied resemblance to the dome of the capitol at Washington. This mountain range being but sparingly watered, has never been convenient to prospect and very little is yet known of it's structure or mineral value. The mines are usually reached from Yuma by driving to Gila City and thence to the mine. from Is to 18 miles east and inland from the river. The claims are numerous. Some have been patented and worked to a depth of 900 feet or more. The veins are re- markedly regular and well formed. The ore is galena carrying about 30 ounces of silver to each ton. The veins trend in a general northwest and southeast course and are nearly vertical The outcrops are in- dicated by outlying masses and weather worn crystals of lOurspar which is the chief veinstone. Calcite and gypsum are also found
 
 secne of quartz dispersed in sheets or combs along the walls or in distinct sheets in the center. Manganese spar and barite arc also as sOciatod in layers. The thickness or power of these veins is usually from to feet sometimes from to l2 feet, wide There are veins also only few inches in width. In general the veins are well filled with ore. This ore occurs in sheets or punches scattered through the vein stone and commonly known among the miners aS ball metal. In one mine in the district a mass of nearly solid ore feet thick was found.
 At or near the water level where the galcnite has decomposed both carbonate and sulpha.e of lead are found associated with pIic-grcCn fuoritc and an abundance Of crys,allized yellow wulfcnito. another occurrence giving evidence Of tho presence Of moly3denum in @alenite.
 Tie rocks of the district are compact fine grained mica and clay slates standing nearly or edge aud traversed by nTmcTouS dilIes or iEtru- sive masses Of a chocolate -colored porphyry.