PEOCEEDINGS OF THE NATIONAL MUSEUM 



VOL. 70 



From these angles the following elements were calculated : 

 p = 0.9135. a=2.357. 



g=2.074. 6=1. 



r=l. c=2.153. 



6=0.2684. ^=105° 34'. 



M=74° 26'. 



The crystals usually show but four forms: c (001), a (100), h (203) 

 and p (111). Other forms noted were s (106), r (102) and Tc (T04) 



(fig. 2). The base is usu- 

 ally the largest face on 

 the crystal and is always 

 more deeply striated 

 than the other prom- 

 inent faces. The face 

 h (203) is broad. The 

 pinacoid a (100) is usu- 

 ally medium in size and 

 is the brightest face on 

 the crystal. The two 

 terminal faces p (111) 

 are badly etched and 

 reflections from them are 

 always poor. Of the 

 other faces s (106) and 

 r (102) were encountered 

 once as narrow striated 

 faces and Ic (T04) three 

 times, likewise narrow 

 and striated. 



PHYSICAL PROPERTIES 



The crystals have a 

 good cleavage parallel to 

 the front pinacoid, a 

 (100). No other cleav- 

 ages could be detected. The crystals are brittle and break easily 

 across the prisms as well as along the cleavage. The crystals easily 

 scratch gypsum; calcite can be scratched by rubbing it across a 

 crystal but fluorite seems to be unaffected. Its hardness then is 

 3 to 3.5. 



OPTICAL PROPERTIES 



Chlorophoenicite is grayish green in color but has a suggestion of 

 pink on the pyramid faces. Under strong artificial light the crystals 

 take on a purplish red or reddish gray color, deeper in tint on the 



Fig. 2.— Orthographic and clinograhic projec- 

 tion OF CRYSTAL OF CHLOROPHOENICITE 



