126 



GEOLOGICAL SUEVEY OF THE TERRITORIES. 



blocks of the other coals. Like them, however, it is almost entirely 

 free from slate and iron j)yrites. Eesin occuis in it in scattered particles 

 and bunches more abundantly than in the coals of the other mines. In 

 1872 the vein was worked from three openings, and up to that time 

 about 8,000 tons of coal had been mined, the average amount being about 

 thirty tons per day. 



A cross-cut from the bottom of the mine driven 70 feet east, gave 

 the following section, the east or upper end being at the top of the sec- 

 tion : 



No. 



Nature of strata. 



Thickness, 

 in feet. 



15 



14 



13 



12 



11 



10 



9 



8 



7 



6 



5 



4 



3 



2 



1 



East end, highest, geologically : 



Sandstone 



Coal 



Clav 



Coal 



Clay 



Sandstone 



Clay 



Black slate 



Clay 



Sandstone 



Clay 



Sandstone 



Coal 



Sandstone 



Clay, (west end, lowest, geologically) 



Main coal bed, total. 



6 

 2 



8 

 2 

 2 

 3 

 4 

 3 

 8 

 7 

 3 

 12 

 2 

 4 

 4 



The eastern sandstone (No. 15) is probably the extension below of a 

 heavy ledge of sandstone, that forms the crust of the ridge. The clay 

 is all fire-clay, of pretty uniform and excellent quality, very similar in 

 appearance to that of the true coal-measures. It is used for the manu- 

 facture of fire-brick in an extensive manufactory at the base of the hill. 

 Dr. Hayden observed near by the following outcrop of the lower lig- 

 nite beds: 



East, highest. 



Eusty yellow sandstone. 



Fire-clay, with one or two unimportant seams of coal, 10 to 15 feet. 



Coal, 8 feet. 



Fire-clay. 



Eusty yellow soft sandstone. 

 West, lowest. 



The clay is used for fire-brick and potter's ware. In the upper bed of 

 sandstone impressions of leaves of deciduous trees are found, among them 

 a Plaianus. In the southern extension of the Golden City beds we pass 

 several openings, one of which is a shaft 70 feet deep, showing the 

 nearly vertical bed to be 5 to 11, and even 14, feet thick of good coal. 



Johnson mine : range 70 west, township 4 south, section 3, shows a 

 bed of coal 7 to 9 feet thick, which is mined from a shaft 90 feet deep. 



Welch and Loveland mine : range 70 west, township 4 south, section 

 3, about a quarter of a mile only south of the Johnson bank ; course, 

 south 50° east to south 48° east ; clip, 71*^ southwest. A drift having a 

 course of north 34° east famished Mr. Berthoud with the following sec- 

 tion : 



