CHAPTER IV 



DETERMINATIVE TABLE 

 PART I 



MINERALS WITH METALLIC, OB SUB-METALLIC LUSTEB 



ALL minerals included in this section yield a streak dark in color, 

 and when finely ground the color of the powder is also dark. If 

 coarse pieces with thin edges are held between the eye and the yel- 

 low flame of the burner, they will appear perfectly dark, and the 

 thin edge will transmit no light. In some species one specimen may 

 be of sub-metallic luster, while another specimen may be of a non- 

 metallic luster; such minerals will be found in both Part I and 

 Part II. 



A fragment of the mineral is heated on coal in the 0. F. and R. F. 

 alternately; it yields a coat. 



I. The coat is white, and while being heated the assay yields a 

 garlic-like odor (arsenic). The presence of arsenic may be proven 

 by the tests on p. 585. Minerals on p. 620. 



II. The coat is white and when heated in the inner blue cone of 

 the 0. F. colors it yellowish green (antimony). The presence of 

 antimony may be proven by the tests on p. 584. Minerals on 

 p. 623. 



III. The coat is white and colors the flame bright green (tel- 

 lurium). The presence of tellurium may be proven by the tests 

 on p. 587 Minerals on p. 625. 



ABBREVIATIONS USED IN THE TABLE 



I. 

 II. 



Crystallization isometric. 

 Crystallization tetragonal. 



III. Crystallization hexagonal. 



IV. Crystallization orthorhombic. 



V. Crystallization monoelinic. 



VI. Crystallization triclinic. 

 Amorph. Amorphous. 



B. B. Before the blowpipe. 



C. Color. 

 Cl. Cleavage. 



F. Fusibility, fusee. 



G. Specific gravity. 

 H. Hardness. 



O. F. Oxidizing Same, 

 p. Page. 



R. F. Reducing flame. 

 Soda. Sodium carbonate. 

 S. Ph. Salt of phosphorus. 

 Str. Stn-:ik. 



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