14 Journal of thp: Mitchell Society [June 



rowing to minute seams along the strike and also in depth. These 

 lenticular veins, however, may be found to be 100 or more feet 

 in depth and then be connected by a narrow seam with still 

 another. They are known also to occur from 100 to 400 feet 

 in length and then be connected by narrow seams, or be adjacent 

 to other lenses of barytes. The deposit does not always 

 represent a solid vein, but is more apt to contain a main seam 

 of barytes with smaller seams on either side and approximately 

 parallel to them, the different seams of barytes being separated 

 by bands of the schist rock. The general strike of the schist and 

 also of the barytes veins is in a general I*^. E. and S. W. direc- 

 tion and they are pitching at very steep angles. There is usually 

 accompanying the barytes more or less quartz, which, however, 

 is found either on one side or the other of the seam of barytes. 

 Occasionally it is intermixed with the barytes ; then again, the 

 fissures and crevices may be filled almost entirely with quartz 

 with little or no barytes, but the quartz can usually be traced 

 almost continuously for long distances in the direction of the 

 strike of the schists and seams. Thus, at nearly every open- 

 ing in which barytes has been found, quartz was the mineral 

 that outcropped on the surface, the barytes being encountered a 

 few feet below and to one side of the quartz. 



EUTILE 



The only rutile that is mined in this country is at Roseland, 

 Virginia.^ The rutile occurs in irregular bunches in a gneiss 

 that rises in a bluff 40 to 50 feet above the Tye River and has 

 been mined in four open quarries for a length of about 300 feet. 

 Along this bluff the ore occurs in very irregular masses, some of 

 it being nearly pure dense white feldspar with streaks and 

 patches of rutile, and at other times in the form of small grains 

 about the size of wheat. This ore yields about 5 per cent of rutile. 

 Occuring in both the ore and the gneiss are seams and specks of 

 opalescent blue quartz about one-half an inch across. At the 

 lower or southeast end of these workings the ore contains about 

 10 per cent of rutile, but it also contains manaccanite which 

 cannot be removed by the present method of concentration ; but 



"Virginia Geological Survey, Bulletin III-A, 1913. 



