THE NONMETALLIC MINERALS. 



449 



of the fissure was nearly north and south, and at the time of making 

 the report noted (1876) it had been developed to a distance of some 

 300 feet. The material is described as more uniformly lustrous than 

 that from Ritchie County, and of a greater coherence, though none the 

 less distinctly cleaved and jointed. An analysis of a sample from the 

 Cristo mine, as given, yielded results as follows: 



Specific gravity 1 . 156 



Volatile matter: 



Illuminating gas 63. 32 



Sulphur 0. 46 



Water 0.36 



64. 14 



Coke: 



Fixed carbon 31.63 



Sulphur 0. 37 



Ash 5.86 



37.86 



100. 00 



Carbonite or natural coke is the name given to a peculiar hydro- 

 carljon compound occurring in the form of beds like bituminous coal, 

 in Chesterfield County, Virginia, and having a dull black and, for the 

 most part, lusterless aspect, somewhat resembling coke. (Specimens 

 Nos. 63499, 63500, U.S.N.M.) 



An analysis by Wurtz^ yielded the following: 



Per cent. 

 Coke 84.57 



Volatile combustible matter 15. 43 



Other analyses by Dr. T. M. Drown ^ on two portions, the one dull 

 and lusterless and the other lustrous, yielded: 



Occurrence. — The material occurs interbedded with shales much like 

 ordinary bituminous coal, there being, according to Raymond, three 

 distinct beds varying from 1 foot 9 inches to 9 feet in thickness, inter- 



^ Transactions of the American Institute of Mining Engineers, III, 1875, ix 456. 

 2 Idem, XI, 1883, p. 448. 



NAT MUS 99 29 



