The quicksilver resources of California . ^ if not exclusively, consisting of car-bon dioxide, which in that drift were so strong as to force the SANTA CLARA COUNTY. 183 company to abandon the work. It is generally supposed thatthis gas is generated by the decomposition of the calcite anddolomite, which are abundant in those parts of the mine, bothin the vein filling and in the alta. In order to give an intelligible description of the formationof the ore bodies in the New Almaden mine, the old works, atpresent inaccessible, must be taken into account. The magnifi-. PHOTO No. 20. RANDOL SHAFT,
The quicksilver resources of California . ^ if not exclusively, consisting of car-bon dioxide, which in that drift were so strong as to force the SANTA CLARA COUNTY. 183 company to abandon the work. It is generally supposed thatthis gas is generated by the decomposition of the calcite anddolomite, which are abundant in those parts of the mine, bothin the vein filling and in the alta. In order to give an intelligible description of the formationof the ore bodies in the New Almaden mine, the old works, atpresent inaccessible, must be taken into account. The magnifi-. PHOTO No. 20. RANDOL SHAFT, NEW ALMADEN. cent map of the underground works in the office of the com-pany gives ample opportunity to do this. A reduced copy ofthis map, up to the date of its publication, 1887, is found insheet IX of the atlas of Mon. XIII, U. S. G. S. The accom-panying plan [Fig. 57] gives an outline of the ore bodiesopened up in the mine. The later works are located princi-pally in the upper levels. One nearly continuous series of ore bodies {a) lies on a line 184 QUICKSILVER RESOURCES OF CALIFORNIA. Starting near the main shaft and going in a northwesterlydirection to about 400 feet northwest of the Santa Rita shaft,a distance of about one fourth of a mile. These ore bodies areworked to a depth of not over 700 feet below datum level (topof Mine Hill). In the southern part, near the main shaft, theore bodies are intricately overlying each other. [See Fig. 57,crosscut AA, a west-east section over this part of the mine.]This may be due to the intrusive serpentine body i
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectminesandmineralresou
