376 



GEOLOGY OE THE DENVER BASIN. 



in all cases where feasible the coal ordinarily left for support to the roof was 

 included. Whenever the coal appeared to show physical differences in its 

 natural position in the mine, or where statements as to supposed or actual 

 differences were made by the mine superintendent, separate samples wen- 

 taken for purposes of study. To obtain a fair average the samples were 

 equably distributed throughout the mine. 



CHEMICAL ANALYSES OP THE COALS OF THE DENVER BASIN, ARRANGED 

 ACCORDING TO MIMING DISTRICTS. 



Table I. — Analyses of coals of the Denver Basin. 



En. I .uilieM . 



Mitchell . 



Area easl >>i 



New Boulder Val- 



ley. 



Progn bs 



Star 



.do . 



Jackson 



....do .... 



Sir;.. ;!■ 1 



Volatile 

 com- 

 busti- 

 ble. 



Per :i Per ot. 

 42.34 37.81 



t tladstone 



Simpson Spencei 



...do 



...do 



44.7:i 

 43.80 



44. 51 



45. 15 

 II 69 



4". 55 

 4 I. 62 

 IT B6 

 44.63 



4;:. 80 



44. 68 



41. '.IT 



45.62 



44.4:; 



44.74 

 44. 55 

 43.77 

 45.30 

 44.86 

 44. 16 

 15. 26 

 43.00 



44. 08 

 4;'.. 05 

 43.90 

 14 98 



45. Ill 

 45.16 

 44. 56 

 43.80 

 44.34 

 46.15 



32. 10 



32.51 

 33.37 

 32.34 



33 "1 

 31 35 

 10 .-J 

 34.51 

 34.14 

 34.59 

 33.43 

 34.54 

 32.63 

 34.98 

 33.85 

 33.84 

 33.81 

 33. 12 

 34.03 



33. 80 

 32. 53 

 33.28 

 34.67 

 34.41 

 36.70 

 37. 82 

 37.81 

 38.18 

 37. 09 

 37.87 

 34.65 



16.64 



18.54 

 17.03 



Hi. 04 

 17.61 



16.42 



17.75 

 17.25 

 16.80 

 17. 03 

 17. Hi 

 17.25 

 15.44 

 18.32 

 16.38 



17, 58 



15. ii7 

 16.76 



17 ill 



16. 06 

 17.01 

 Hi. 84 

 18.38 

 16.38 

 17.75 



18. 7'. 1 

 13.42 

 13.04 

 13.47 

 14.74 

 13. 57 

 16.27 



Perot 

 4.95 



1.99 



5.35 



4.25 

 5.53 



3.55 

 3.52 

 4. 53 



3. 25 



n 



3.76 

 3.97 

 3.38 

 3.48 

 3.84 

 3.60 



4. 22 

 4. 39 

 3.52 

 6 IT 



::. 72 

 :i.4C 



3.45 

 4.65 

 3.66 

 3.99 

 3.84 

 I 82 

 I 12 



r, ,-t 



II. 40 



5 ,11.. 



ray . 



Ligbl \ rllow 



Yellow-white — 

 Reddish-white. .. 



White 



White, slight ml 



tint. 

 Fellow white — 



.do . 



Specific 

 gravitj ;.i 

 degrees i' 



Ked 



Lighl yellow. . . 



Yellow 



Red-yellow 



Lighl \ .41uw. . . . 



White 



Slightly reddish 

 Reddish 



do 



Reddish \\ bite . . 



I . i Li I ■ t red 



Reddish 



Light red 



Red 



Fellowish-gray. . 



Reddish 



....do 



Fellowish-white. 

 JTellowish-gray 



.do . 



Light gray.. 



....do 



Brow n grai 



1 341 ,i 13.0 

 1.336 a 12.0 



1.335 B 10.0 

 1. 350 @ 10. 5 



1.386 •■ ii" 



1.333 .■ 15 .. 



1.345® 12.0 

 1.331® 12. 



1.336 w 11.0 



1. 328 ® 12. 

 i.339 2 12.0 



1. 5 19.0 



1 330 5 19 ,. 

 1 334 i i.-.:, 

 1.331 5 12.5 



1.334 a H.ii 

 1.350 « 12.0 



1.335 ,i 13.0 

 : .'.i a 16 .' 



._■ I : " 



1.324 a 5.5 

 1.341 a 8.0 

 1.329 a 13.0 



I. 16 , 21 - 



1 . 35 a 19. 4 



1.35 ./ 17.5 



1.33 

 1.37 

 1.37 

 1.35 



1.29 



1.29 



1.35 

 1 . 32 



1.26 

 1.34 



1.34 



1.32 

 1.30 

 1.28 

 1.22 

 1.19 

 1.19 

 1. 17 

 1.18 

 1. 17 

 1.33 



