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tilHUi n I 
164 ECONOMIC GEOLOGY OF SILVERTON QUADRANGLE, [bull. 182. 
has been $1,200,000. The lode on the North Star property is a strong 
stringer lead, consisting- of a zone of country rock traversed irregu- 
larly by ore-bearing stringers. At the croppings, near the summit of 
Little Giant Peak, this zone is about 100 feet wide. The vein as a 
whole has no walls, and the stringers are usually not accompanied by 
gouge. The country rock is that found in the Silver Lake Basin, and 
belongs to the Silverton series. The hard, massive sheets of andesite 
are found to be less favorable for the deposition of ore than the softer 
breccias. The character of the lode makes it very difficult to work. 
Ore-bearing stringers may be encountered anywhere within the zone 
of fissured country rock, and frequent crosscutting is a necessity. 
The reduced horizontal projection of the levels, shown in fig. 13, will 
give some idea of the irregular character of the workings. The pay 
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FEET 
■*"• © ico aoo 300 4-00 300 600>) 
Fig. 13.— Sketch plan of underground workings of the North Star (King Solomon) mine. 
shoot as a whole pitches to the southeast, apparently at an angle of 
about 45°. The upper 200 feet, near the surface, was largely sulphate 
of lead (anglesite) not carrying much silver. This changed in depth 
to galena, which was associated with increasing amounts of tetrahe- 
drite as the ore was followed downward. In the lower levels the galena 
was subordinate to the gray copper. This was the most valuable ore 
mineral in the mine, being a highly argentiferous tetrahedrite, or the 
variety of gray copper known as freibergite. Below the fifth level 
the pay shoot failed, although the fissure continues. No serious pros- 
pecting has yet been undertaken to determine whether there may not/ 
be other ore bodies beneath the pay shoot. That there are such ore 
bodies is rendered probable by the fact that ore similar in character 
to that of the North Star mine occurs at a lower level in the Dives 
mine, which adjoins the former on the southeast. The gangue of the 
North Star ore was quartz. Some gold occurred occasionally in the 
