14: R. Arnold — Rocks from the Sawtooth Range. 



zone 650 feet long with an average width of 12 feet. He also 

 states that ore of this same class occurs on adjacent claims. 



Impure gray chert carrying small amounts of chalcopyrite 

 and malachite, and coated with considerable quantities of 

 manganese oxide, occur with a decomposed mineralized igne- 

 ous rock at the Black Trail claim, about 2 miles west of Mt. 

 Skokomish. 



The relation existing between the mineral-bearing and 

 country rocks in the Sawtooth Range is typically illustrated by 

 the section at Smith's camp, which is as follows : 



Geologic section at Smith's Camp, from east to west. 



Feet 



Diabase ._ 20 + 



Quartz vein 8 



Diabase _ 50 



Quartz vein ,. 20 



Semi-metamorphosed black schist, mineralized near 



contact with vein _. 10 



Alternating vertical beds of hard sandstone and shale 



or slate 10 



Quartz vein 4 



Sandstone and shale = . 20 + 



One wall of nearly all the veins in the district is igneous 

 rock while the other may be schist, chert, calcareous chert or 

 also igneous rock. 



From the character of the specimens examined, it seems proba- 

 ble that the ores in this region consist largely of mineralized 

 contact vein quartz with which is associated some of the country 

 rock that has been locally mineralized along contacts with veins 

 or contacts with intrusive diabase or other basic rocks. The 

 most valuable ore in those veins which are associated with the 

 iron-bearing cherts is usually immediately adjacent to the 

 igneous wall. Next to the igneous wall in some of the veins 

 is a zone from 4 to 12 inches or more in thickness, filled with 

 decomposed iron ore ; this zone extends for several feet below 

 the surface and represents a zone of sulphides farther down. 



According to Mr. Stanard, the belt of igneous and associated 

 copper-bearing rocks extends at least as far as Mt. Constance 

 in Sees. 6 and 7, T. 26 K, R. 3 W., 15 miles northeast of Mt. 

 Skokomish. 



