IQlJf-^ Certain Mineral Resources 115 



The greisen veins in which the tin occurs traverse the granite 

 in all directions and are dipping at very steep angles. The 

 width of these veins is usually from 8 to 12 inches, though 

 some were observed that were several feet in thiclaiess. The 

 cassiterite is occasionally concentrated into seams from 1 to 

 2 inches wide and is associated with pyrite and arsenopyrite, 

 the rest of the gangue of the veins being composed of quartz 

 and mica. The jJi'incipal work was done here about twenty 

 years ago, and a concentrating mill was erected on the property 

 and about 290 tons of rock were tested. It is reported that 

 about 2,400 pounds of tin concentrates were shipped to Boston, 

 but that they only averaged about 43 per cent, of metallic tin, 

 due to the concentrates being contaminated with arsenopyrite 

 and ilmenite. There was not sufficient work done on the prop- 

 erty to definitely determine whether or not there existed a com- 

 mercial deposit of cassiterite. 



Texas: — Oassiterite has been found in Texas on the east 

 flank of the Franklin Mountains, the southern extension of the 

 Organ or San Andreas Range, about 10 miles north of El 

 Paso. These deposits were discovered in 1899 and had been 

 prospected to a depth of about 50 feet. The ore occurs in well- 

 defined veins, which have a strike approximately east and 

 west, which is nearly at right angles to the direction of the range 

 and are dipping toward the north at very steep angles. There 

 have been three veins discovered here, which have been exposed 

 by pits and open cuts for several hundred feet along the strike. 

 The veins occur in the granite and are considered by Mr. W. 

 H. "Weed to be the result of deep-seated agencies and that fur- 

 ther exploration will develop well-defined tin veins. 



Chapel Hill, N. C. 



