UNIVERSITY OF CALIFORNIA PUBLICATIONS 



BULLETIN OF THE DEPARTMENT OF 



GEOLOGY 



Vol. 4, No. 17, pp. 41 1-423 ANDREW C. LAWSON, Editor 



NOTES ON THE FOOTHILL COPPER BELT 

 OF THE SIERRA NEVADA. 



BY 



A. Knopf. 



CONTENTS. 



Introduction : 411 



Speneeville, Nevada County, and Vicinity 412 



Pine BHD, Nevada County 413 



The Valley View Group 414 



Dairy Farm Mine 414 



Valley View Mine : 41.5 



Cedar Mine, near Wolf Creek 415 



Campo Seco, Calaveras County 415 



Copperopolis, Calaveras County 41S 



Napoleon Mine, Calaveras County 422 



Resume 423 



INTRODUCTION. 



The existence of a belt of copper deposits along the western 

 foothills of the Sierra Nevada has long been known, but its 

 economic importance has been overshadowed by the richness of 

 the Gold Belt immediately to the east of it, and by the extensive- 

 ness of the copper deposits of Shasta County. 



Owing to the discovery of rich carbonate croppings in Cala- 

 veras County, California experienced an intense copper excite- 

 ment as early as 1861. Upon the exhaustion of the oxidized ores 

 a period of stagnation and idleness ensued, lasting well up to the 

 present time. Only within the past decade has an extensive 

 exploitation of the unaltered sulphide bodies commenced, notably 

 at Campo Seco and Copperopolis.* 



* For an account of the historical and economic features of the copper 

 resources of the State, Bull. 23 of the Cal. State Mining Bureau should be 

 consulted. , 



