482 W. E. Hidden and J. B. Mackintosh — Tttria and 



Specific Gravity = 



UOs.... 



42"04£ 



IK)- 



23 89 



ThO a .. 



4-76 



T 2 3 ... 



6-87 



Er 2 O s -. 



3-47 



Ce 2 3 .. 



233 



Fe 2 O s .. 



1-05 



EeO.... 





CaO ... 





PbO 



11-31 



Si0 2 ... 





HoO.... 



4-28 



Cleveite. 



7 - 49. Oxygen Katio. 



17-56 

 3-61 

 9-03 s 

 2-73 

 2-16 

 2-00 



5-07 



43-79 

 i 21-17 1 



^42-16 



.20-99 J 



23-78 



Broggerite. 

 Specific Gravity = 8 73. Oxygen Ratio. 



40-44 



-44-18 



100-00 



38-82^ 







41-25 

 5-64 



3033 

 4-28 



• 34-61 



2-42 



3 18 " 





0-35 



0-33 











- 9-57 



1-26 



1-75 





0'-30 



0-54 





8-41 



3-17 





0-81 



2-70 



0-83 



4-61 (neglect) 



100-09 



In the broggerite analysis a small amount of silica occurs, 

 which if supposed to exist as admixed silicate will reduce the 

 excess of basic oxygen. Neglecting the water in broggerite 

 the oxygen ratio for these minerals will be therefore : — 



Bases. 



R0 2 (R0O3RO) 



1 1 



U0 3 

 2 



H 2 



Cleveite, • — 1 — ^ 



2 

 Broggerite, 1 1 



The comparison of the three formulae shows the relationship 



clearly (RO including E0 2 and R 2 3 ), as follows : — 



Broggerite 



Cleveite 



Nivenite 



3RO, UOs. 



6RO, 2UO3, 3H 2 0. 



9RO, 4U0 3 , 3H 2 0, 



We have named this mineral nivenite, in recognition of the 

 energy which Mr. Niven has displayed at this locality, and the 

 assistance which :he rendered us in obtaining the material for 

 investigation. 



Fergusonite. 



This heretofore rare mineral occurs in large quantity at this 

 new locality. Up to this date we have received over seventy 

 kilos, some masses of which weighed over a pound. Broken 

 prisms, rough in form, rarely showing terminal planes and 

 masses of crystals interlacing each other is the manner of occur- 

 rence The immediately associated minerals are cyrtolite and 

 thoro-gummite and also magnetite. The gadolinite also 

 sometimes encloses it. It also occurs alone in a matrix of or- 

 thoclase or of quartz. One large mass of this kind of gangue, 

 upon being broken up, yielded over thirty kilos of pure 

 mineral in the form of fragments, most of which were basal 

 sections of crystals which had been originally four to eight 

 inches long and about 1-J cm thick. 



