380 QTTICKSILVER DEPOSITS OF THE PACIFIO SLOPE. 



tains Miocene sandstones and heavy gravels snpposed to be Pliocene. 

 Both of these formations have been greatly distnrbed and often stand at 

 high fingles. The nietanioi'phic rocks near Panoche Pass contain a number 

 of deposits of quicksilver, some of which have yielded metal. 



Tlie Stayton mines was the name given to a group of fourteen prospects, 

 which are remarkable because they contain stibnite in quantities equal to or 

 greater than those of cinnabar. At one time quicksilver was reduced in a 

 retort at this locality and at another the antimony ore was smelted The 

 mines have not been in operation for some years and little could be seen at 

 the time of my visit, excepting that both minerals occurred in proximity, 

 chiefly with quartz gangue, in siliceous and serpentinized rocks of the usual 

 type. I saw no indications of a large or a regular deposit. The Wonder 

 quicksilver mine was close to the Stayton and is said to have been similar. 

 About eleven miles west of Panoche post-office, near the main high road, 

 is a prospect called the Cerro Gordo. It is remarkable for the presence of 

 metacinnabarite in the ore, which contains, besides, cinnabar, pyrite, and 

 bitumen, associated with opal and crystalline silica. The inclosing rocks 

 are of the metamorpliic series and contain titaniferous magnetite. The 

 material on the dumps seemed to me of a promising character. 



The Little Panoche mine is in a canon at the north end of Little Pano- 

 che Valley. The workings were never large and are now for the most part 

 inaccessible. The rock is uietamorphic sandstone, highly silicitied, but ac- 

 companied by only trifling quantities of serpentine. The ore, as shown by 

 the dumps, consisted of cinnabar and pyrite in a quartz gangue, with meta- 

 morpliic sandstone. I saw no evidence of a defined vein, though the work- 

 ings may have disclosed something of the sort. 



The Ceri-o Bonito, sometimes called the Panoche Grande, is about 

 three miles by road from Panoche post-office, in the northwestern corner 

 of Fresno County. It lies close to a basalt area of considerable size, the 

 only one of the kind known to me in this part of the country. The mine 

 is in metamorpliic sandstone, accompanied by serpentine, and the ore is 

 associated with quartz and calcite. Very little pyrite exists in the dumps 

 and the ore was dull, unpromising-looking material. According to Mr. L. 

 Janin, the ore followed the stratification. The most promising ore-liearing 



