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UNIVERSITY OF VIRGINIA PUBLICATIONS 



(1), together with analyses of the mineral from North Carolina (II), 

 Sweden (III), and Canada (IV). 



Analyses of Cyanite. 



I. Cyanite collected by Thomas L.Watson from Graves Mountain, Lincoln County, 



Georgia. J. Wilbur Watson, analyst, 

 la. Molecular ratios from 1. 

 11. Cyanite, Lincoln County, North Carolina. (Smitla and Brush, Ame)\ Jourii. 



Sci., 1853, vol. 16, p. 371.) 



III. Cyanite, Horrsjoberg, Sweden (Ingelstrbm, Journ. prakt. Chem., vol. 64, p. 61). 



IV. Cyanite, British Columbia. (Hoffman, Rept. Geol. Surv. Canada, 1878-79, p. 1.) 



Hematite. Hematite was observed as an important constituent of the 

 rock at all the openings from which rutile had been won. Together with 

 cyanite and less quartz it forms the rutile matrix, which according to Shep- 

 ard* marks a band 50 feet in thickness. The hematite is massive granular, 

 steel-gray to red in color, has filled in the spaces between the blades of 

 cyanite, and presents a somewhat roughened surface. At times it presents 

 an open or cellular texture due, according to Shepard, to "including the 

 decomposing ferruginous cyanite, particles of pyrophyllite, and even por- 

 tions of compact rutile." The ratio of hematite to cyanite is variable, 

 sometimes one sometimes the other mineral is in excess. On weathered 

 surfaces cyanite and quartz stand out in relief. 



Thin sections show an aggregate of cyanite blades and steel-gray hem- 

 atite, with some quartz and rutile. Hematite fills the cyanite interspaces 

 and is formed as rims around, and along the cleavage and fracture direc- 

 tions in, the cyanite. Rutile occurs as inclusions in the principal minerals. 

 Cyanite is partly altered to muscovite, and in some hand specimens the 

 cyanite individuals are more or less curved and bent. 



* Op. cii., 1859. 



