186 C. Palache — Mineralogy of Franklin Furnace, JV. J. 



The ratio Ca : Si : (0 + F 2 ) - - 2:1:4 very nearly, leading to 

 the formula Ca 2 Si (O, F 2 ) 4 . This is the formula suggested by 

 Dana (System, 529) for cuspidine, in which fluorine is treated 

 as replacing oxygen. No other treatment of the analytical 

 data gave a satisfactory ratio. It is much to be regretted that 

 no further material remains for more complete physical deter- 

 mination of this interesting species. 



JTumite: Crystal Form. 



Minerals of the humite group have long been known from 

 Franklin under the name of chondrodite. They have not been 

 analyzed nor till recently have good crystals been found. In 

 1906 were found orthorhombic crystals of deep orange-red and 

 pale yellow color which yielded contact measurements accurate 

 enough to prove the material to be humite. 



Forms : b (010), o 2 (210), m (110), e 6 (102), » a (112), i\ (214). 



Combinations : 



1. b, o a n a , r 4 . 



2. b, o 2 , e 6 , n a , r 4 . 



3. b, o 9 , m, e 6 , n Q9 r 4 . 



Leucophcenicite : Crystal Form. 



Leucophoenicite was described by Penfield, whose material 

 did not permit him to determine the system to which the crys- 

 tals belong. From its relation in composition to the humite 

 group he believed it to be monoclinic. 



Crystals of measurable quality very kindly placed in the 

 writer's hands by Mr. Canfield, furnished data for the determi- 

 nation of system and forms. 



System, monoclinic: — Axial ratio : a : b : c = 1-1045: 1 : 2*3155. 

 P z= 76° 44'. 



Forms : 



c 



(001) 



s (120) 



x (103) 



y (103) I (121) d (123) 



b 



(010) 



e (101) 



r (101) 



o (011) n (121) h (123) 



a 



(100) 



/0«2) 



» (102) 



f (012) u (122) a (124) 



in. 



(110) 









The crystals are of epidote habit, elongated parallel to the 

 5-axis, the orthodome zone deeply striated. Crystals are 

 twinned on a face in this zone which was taken as the basal 

 pinacoid, the two individuals frequently interpenetrating. The 

 form series is peculiar and could not be correlated in any way 



