1915'] The Coggins Gold Mine 167 



mineralogical character of the ore 



The ore consists principally of free gold, with some pjrite 

 and a gangue of white quartz or silicified slate, or both. The 

 pyrite seems to be more or less disseminated through the schists 

 and carries some gold, which it is believed is largely in the free 

 state. The seams of slate that occur in the vein are also impreg- 

 nated with small particles and crystals of pyrite, although their 

 gold content is often very low. These barren portions vary in 

 width from a few inches to several feet. 



A small amount of calcite has been observed in the quartz 

 seams, and a very small amount of arsenopyrite. 



The veins are altered usually to a depth of 50 to 70 feet, 

 but in some instances they are partly altered to a still greater 

 depth. 



Veins. — There are two so-called veins that have been de- 

 veloped : one known as the "East Vein" and the other known as 

 the "West Vein" ; but as far as can be determined, these two 

 are parts of one general ore formation and do not represent two 

 distinct depositions of ore. The two bands of slate impregnated 

 with the quartz veins and seams were supposed to be separated 

 by a band of barren slate, but it was found upon sampling this 

 that it carried a certain amount of gold. 



Developiment Work. — The property has been developed 

 principally by one shaft, with its drifts and cross-cuts. A cer- 

 tain amount of prospecting has been done at other points along 

 the strike of the slates. At the southwest end of the property 

 in a line S. 42° W. from the shaft, a pit (A) about 8 feet deep 

 was sunk along the edge of a diabase dike. At several points 

 between this pit and the shaft, several crosscuts were made, ex- 

 posing the slates, but it did not show any mineral of value. To 

 the northeast of the shaft, several pits have been made, the prin- 

 cipal one being about 400 feet from the shaft, where a pit (B) 

 was sunk 12 or 15 feet, that exposed the slates. This pit was ap- 

 proximately N. 42° E. from the shaft. 



The main shaft was sunk vertically for a distance of about 

 8 feet, and then was turned, following approximately the dip of 

 the slates; and is continued on this incline to the lowest level, 



