THE MINERALS OF IDAHO 61 



In the Highland Valley district near Twin Springs bench gravel 

 deposits are washed with the water from melting snows. The season 

 is only 30 to 35 days annually. The gold is worth $16.02 an ounce. 



The Neal district produced gold to the value of $200,000 previous 

 to 1898 from veins in fault fissures and along minor shearing planes in 

 granite. The gangue is quartz and sulphides are common. Spongy 

 skeletal gold is common in the oxidized ore. The gold is worth $15 

 an ounce. 



The Pine Grove district has produced some gold from quartz veins 

 containing auriferous sulphides. 



The Rocky Bar district was originally an important placer camp, 

 but in 1895 was reported to be worked only by Chinese. Lode 

 deposits have been mined in the Old Alturas, Idaho, Vishnu, and 

 other mines. The ores consist of quartz containing auriferous sul- 

 phides in the primary ore and oxidation products with native gold 

 above. The gold of the veins is worth $14 an ounce. Specimens of 

 primary ore from the Vishnu mine (Cat. Nos. 14761-14762, 

 U.S.N.M.) consist of auriferous sulphides in quartz and of the 

 oxidized ore (Cat. No. 14763, U.S.N.M.) contain gold in rusty 

 quartz. A sample of placer gold (Cat. No. 55469, U. S.N.M.) con- 

 sisting of very pale colored unworn gold is labeled as from Dry Creek 

 above Loom Creek, Elmore County. 



IDAHO COUNTY 



The Big Creek district contains large low grade gold deposits which, 

 mineralogically, are very uninteresting. The Goldman and McRae 

 and Moore are the principal mines. 



In the Crooks Corral district some placer gold is obtained by 

 hydraulicking bench gravels of the Snake River side of the high 

 divide between Snake and Salmon Rivers, which are here only 12 

 miles apart. The deposit has been found in places to be very rich, 

 but the work is retarded by the high elevation and scarcity of water. 

 The gold is 0.954 fine (95.40 per cent Au). 



In the Dewey (Iiarpster) district, gold is produced from ores 

 consisting of auriferous chalcopyrite in sihcified greenstone schist. 

 Small lots of the ore are very rich. The Dewey is the principal mine. 



The Dixie district contains both placers and gold quartz veins. 

 The placer gold is 0.820 fine (82 per cent), having a value of $16.95 

 an ounce. There is often more or less cinnabar associated in the 

 sand with the placer gold. The Majestic, Dixie-Royal, Diamond 

 Consolidated, and Monadnock are the principal mines. A specimen 

 of ore from the Mallard Creek property of W. Sendke in this district 

 consists of clean white quartz containing sparingly disseminated 

 auriferous galena and light colored sphalerite. 



