336 GEOLOGY OF THE DENVER BASIN. 



The collar of the shaft is 25 feet west of the outcrop of the western seam, 

 but at the 245-foot level the shaft is 4 feet east of the seam, and at the 

 3 1 7-foot level, 12 feet. Sandstone forms the west wall of the western seam. 

 Slate with sandstone forms the eastern. The eastern seam was but little 

 exploited at the time the mine was examined in the fall of 1890. 



The Golden star mine. — This is Ideated about a mile liortli of ( 'lea r ( "reek, 

 a half mile distant from the New White Ash mine. Two seams are worked, 

 the shaft, which is sunk to the depth of 160 feet, cutting the western at 

 30 feet and at the 130-foot level standing about 15 feet east of it, the 

 distance between the seams being about 33 feet. Fig. F, PI. XVIII, 

 gives the relation of the beds to each other. The strike here averages 

 \. 8° E., with some very slight local deviations, the dip being 80° west 

 (overturned). The walls are of slate or a kind of tire-clay, and sandstone. 

 Both beds are said to occur in the nearer abandoned mine to the north of 

 the Grolden Star, but to be entirely wanting opposite the end of the Dakota 

 hogback, a few hundred yards still farther north. 



The coal of the Golden Star mine is clear, hard, and bright; it is 

 rectangular jointed and shows but a slight amount of pyrite or resin. 



The Rocky Mountain mines Nos. i and i. (Fig. P, PI. XX.) TllOSe shafts are 950 



feet apart, No. 1 being the southernmost and located on the northern 

 slopes of the divide between Clear and Ralston creeks, a i\'\v hundred 

 feet east of the Dakota hogback. Two coal seams are present, their 

 strike being about N. 7° E., their dip 80° to 85° west in No. 1 and 85° 

 to 87 east in No. 2, both observations being taken on the 175-foot level. 

 The east vein in No. 1 shows 3 feet of clear coal in one body, the west 4 

 feet, the distance between the two being 29 feet. In the No. 2 mine, to the 

 north, the east vein is between 3 and 4 feet wide, the west II to 7 feet, both 

 of clear coal. In this mine but 7 feet of rock separates the two seams, 

 while in the old Pittsburg shaft — 7<>0 feet to the north of No. 2 — the two 

 seams are reported to come together, forming one of 11 to 12 feet without 

 parting. 



The coal of these mines is very clean and bright, and but slightly 



fractured. 



