NORTH CAROLINA, GEORGIA, AND MONTANA. 189 



The smaller crystals are often transparent at their extremi- 

 ties. It is, however, in color that the corundum of this locality 

 excels. It is gray, green, rose-color, ruby -red, emerald-green, 

 sapphire-blue, and all intermediate shades to colorless. Many 

 pieces of the blue and red have been cut and polished, pre- 

 senting very good characters as gems, without being of the 

 finest quality. 



DIASPORE. 



"While this mineral is found so abundantly with the corun- 

 dum of Chester, Mass., I have not been able to find it associated 

 with these localities. Several specimens of supposed diaspore 

 have been submitted to me, but on close examination it was 

 found to be colorless kyanite. 



CHLORITE. 



This mineral abounds in this locality, and, as has been stated, 

 is the gangue-rock of the corundum; it not only surrounds the 

 corundum, but permeates it. There are several varieties, vary- 

 ing in color from a yellowish-green to a dark-green, and differing 

 a little in composition. Two specimens from the same locality 

 were composed as follows : 



Large plates. Friable. 



Silica 27.00 29.15 



Alumina 21.60 10.50 



Oxide of iron 16.63 23.50 



Magnesia 22.00 25.44 



Water 12.30 10.04 



MARGARITE (EMERYLITE). 



This curious mica — curious so far as that since my first 

 pointing it out as a characteristic of the emery formation in 

 Asia Minor and the Grecian Archipelago — has been found 

 wherever corundum is, and in the case of Chester emery was 

 the means of leading to its discovery. At the present localities 

 it is abundant and mixed with the rocks and the associate 

 minerals of this locality. Chemical analysis was made of the 

 specimen with the following result : 



Silica 32.41 



Alumina 51.31 



Lime 10.98 



Soda 2.43 



Water 2.13 



