620 CONTENTS. 



CHAPTER III Continued. Page. 

 Tertiary and Pleistocene formations Continued. 

 The valley of Grimes Creek Continued. 



Present stream gravels.. 670 



Bench gravels -- 670 



Older gravels 671 



Lake beds 671 



Volcanic rocks - 672 



The valley of Granite Creek 672 



Configuration ...-_, 672 



Present stream gravels 672 



Bench gravels .- 672 



Older gravels.. 673 



Gravel on the Boise Range 675 



Basalt _ '.... 675 



Fineness of the gold 676 



Water supply... : 676 



Moore Creek 676 



Grimes Creek ... 677 



Granite Creek 677 



Ground available for future work ... 677 



The monazite sands 677 



Relation between placers and quartz veins 680 



CHAPTER IV. The Idaho Basin (continued) 681 



The pre-Tertiary rocks ^. 681 



Granite - 681 



Dikes associated with the granite 682 



The quartz veins 684 



The Idaho City gold belt 684 



The Elaine vein 684 



The Chickahominy vein. 684 



The Illinois vein 684 



The Populist vein 685 



The Cleveland vein... 685 



The Gambrinus (Surprise) vein 686 



The Boulder vein 686 



The Mona MacCarthy vein. 687 



The Sub-Rosa or Forest King vein 687 



The Elkhorn vein... 689 



The Summit vein 689 



The Quartzburg-Grimes Pass gold belt 689 



The Ebenezer vein.. .". 690 



The Gold Hill vein 691 



The Iowa vein 692 



The Carroll veins ..._.- 692 



The Kennebec claim 693 



Veins at head of Wolf Creek 693 



The veins in the porphyry dike east of Wolf Creek 693 



Claims near Grimes Pass _. 694 



Mining districts east of the basin 695 



Fineness of the quartz gold 696 



The geological history of the Idaho Basin 696 



CHAPTER V. The mining districts of the Boise Ridge 699 



Neal mining district 699 



