W. II. Melville — Josephinite, a new Nickel- Iron. 511 



Total 

 Per cent in pebbles. silicate. 



Si0 2 5-14 



A1„0 3 0-33 



Fe 2 3 ... 2-08 



(Ni,Co)0 0-32 



CaO 1*62 



MgO 2-69 



Na 2 0-08 



H\0 above 100° C. 1-12 



Insoluble 



Soluble 



silicate. 



silicate. 



0-23 



4-91 



0-03 



0-30 



0-04 



2-04 



trace 



0-32 



0-06 



1-56 



0-14 



2-55 







0'08 







. 1-12 



13-38 0-50 12 88 



Composition. Insoluble silicate. Soluble silicate. 



Per cent. At. ratio. Per cent. At. ratio. 



Si0 2 45-63 3-04 38-23 2'55 



A1 2 3 6-58 0-39^ 2-34 0'14 ) 



Fe„0, 8-77 0-33 | 15-88 0'60 \ ' 



(Ni,0o)O undetermined J-2-51 2-49 0*07 1 



CaO... 11-03 0-39 | 12-14 0-43 | 



MgO 28-01 1-40 J 19-85 0-99^-2-47 



Na 2 0-35 0-01 | 



H 2 above 100° C, 8-72 0-97 J 



Total 100-02 10000 



/Silicates. — There are two silicates, then, the one soluble in 

 hydrochloric acid being undoubtedly serpentine. This serpen- 

 tine surrounds the metallic portion, and on polished sections 

 its deep green color is well brought out. It has not penetrated 

 into the metallic mass, and it would appear that the pebbles 

 once formed a large aggregation and that fractures took place 

 in directions of least resistance through the serpentine. Other 

 characters of serpentine were noted, its resinous luster, its 

 hardness of about 3, and its infusibility. In the closed tube 

 water was given off. The atomic ratio of the combined bases 

 and water to silica is 3*2 : 2*55 or 5 : 4, a ratio which is identi- 

 cal with that of serpentine. The ratio between bases and 

 water, 7 : 3 instead of 3:2, is not the true ratio for these con- 

 stituents in serpentine as it exists in the pebbles, because the 

 analysis is calculated from figures obtained from material 

 which was dried at 100° C. Again the reddish brown colora- 

 tion of this dried material indicated the presence of some 

 impurity, probably oxides, and this could not be eliminated. 

 The water is, therefore, too low and the iron oxide too high. 



The insoluble silicate, however, cannot be so clearly made out. 

 Its atomic ratio, Si0 2 : base = 6:5, brings it nearer an ortho- 

 silicate than a metasilicate. It is light brown, vitreous, hard, 

 compact and not cleavable. It does not fuse before the blow- 

 pipe. It is not so hard as olivine and its insolubility in acid 



