94 JoUKlSrAL OF THE MiTCHELL SoCIETY [AugUSt 



Oligoclase* (Feldspar) 

 Opal (var. Hyalite) 

 Orthoclase* (Feldspar) 



Phosphuranytile (Uranium mineral) 



Pyrite 



I'yrope (Garnet) 



Pyrophyllite 



Pyrrhotite 



Quartz* (Massive, crystallized and smoky) 



Rogersite 

 Rutile 



Samarskite* 

 Spessartite (Garnet) 

 Sphene (Titanite) 

 Spodumene* (var. Hiddenite) 



Tantalite 



Thulite (var. of Zoisite) 



Titanite (Sphene) 



Topaz 



Tourmaline (Black) 



Uraninite* 



I Gummite 



Uranium Minerals { Phosphuranytile 



J Uranmite 



(^ Uranotil 

 Uranotil 



Xenotime 



Yttrialite 



Zircon* 



Zoisite (var. Thulite) 



A number of the minerals in the above list are described 

 below in considerable detail while others are but briefly 

 mentioned. 



KAOLIN^ FELDSPAR AND QUARTZ. 



One of the alteration products of the feldspar of the peg- 

 m'atitic dikes is k&olin. Some of the finest kaolin produced in 

 the United States is obtained from the decomposed pegmatites 

 in North Carolina, South Carolina and Georgia. These kao- 

 lins usually burn to pure white and are used in the manufac- 

 ture of some of the finest china ware, enameled brick, etc. 



In some of the dikes the feldspar is not altered at all and 

 such dikes in Virginia, North Carolina, and Georgia are being 



