368 QUICKSILVER DEPOSITS OF THE PACIFIC SLOPE. 



that the reck has been greatly disturbed and that wherever a fissure was 

 produced the ore-bearing solutions penetrated. 



The fact that native sulphur occurs in the mine in considerable quanti- 

 ties, taken in connection with the adjacent springs, is sufficient proof that 

 the deposit is due to the action of hot sulphur waters. In mineralogical 

 composition the ore is similar to that of most of the quicksilver mines, except- 

 ing in the fact that it carries gold in such quantities that the mine has been 

 worked for this metal As has been seen in former chajjters, gold occurs 

 in much smaller quantities at Sulphur Bank, Knoxville, and Steamboat 

 Springs. The Manzanita forms a link between cinnabar and gold mines 

 and shows that both minerals may be deposited from the same solutions, 

 not merely in traces, but in notable quantities. No volcanic rock is known 

 to exist within several miles of the Manzanita, but the very hot sulphur 

 springs seem ample evidence of volcanic agencies. It is important to note 

 that this manifestation of volcanic activity with attendant ore deposition is 

 found at a distance from lavas, so that, were the spi-ings to dry up and the 

 country to be somewhat eroded, no direct evidence would remain that any 

 connection ever existed between this deposit and the eruptive phenomena. 



The Buckeye and the Abbott's mines are near the Manzanita, and each 

 of them has produced some quicksilver, the latter over two thousand flasks. 

 Mr. W. A. Goodyear visited these mines. He describes the ore as consist- 

 ing of cinnabar accompanied by pyrite, marcasite, and chalcedonic silica. 

 The ore lines cracks and seams and impregnates earthy matter. Associated 

 with the ore is a considerable quantity of the black oval so often referred 

 to In the i)receding pa.ges.^ 



The Baker mine.. — Tlils miuc Hcs about lialf-wav between Lower Lake and 

 Knoxville. It was visited by Mr. Goodyear, who found metacinnabarite in 

 the ores. A specimen of marcasite which I collected at this mine was ex- 

 amined for gold and was found to contain it, the quantity being about one 

 dollar per ton. 



The Mayacmas district. — A vcry large part of the many cinnabar deposits 

 north of the Bay of San Francisco are found along the Mayacmas Range, 

 which extends in a northwesterly direction from Mt. St. Helena. Two 



' Geol. Survey Califoruin, Geology, vol. 2, appendix, p. 1'24. 



