MINERALS FROM NEW CALEDONIA. 243 
Mica.—From the Balade mine, in the form of white silvery plates, 
some of which are about half an inch in diameter; but no well- 
developed crystals were et Shee by transmitted light the thicker 
plates present a dull greenish shade. Disseminated through 
of the masses of mica are sitll red translucent crystals of garnet, 
and between ms plates of mica films of garnet have occasionally 
crystallized ou 
Plates of this silvery white mica are also found sparsely scat- 
tered through the glaucophane, especially in the glaucophane 
g the garnets ; in other cases again, the mica is in excess, 
the glaucophane playing a subordinate part. 
On Sear this mica was found to have the following com- 
position Sp. gr. 2:938. 
Analysis. 
The e following analysis was prepared on a very small quantity of 
the material, as it was onl ly possible to collect a very limited amount 
of this silvery w white mica; hence much importance cannot be 
attached to i 
4°31 
Sili 50°60 
Alu 25°28 
Iron protoxide 3°47 
Man, anganese [ protoxide 0°50 
Lime 1 boa 
Magnesia 4° 
Potesh 6°69 
tem 2°49 
Ss 0°76 
100-00 
Neither lithium nor fluorine were present. 
The above results do not quite agree with any published 
analysis, nor do they afford a woe iggn formula; but it is 
Analyses. 
Water, combi 4:50 446 
ai combined ....,. "YT aera ge i ees ee ee i 
NE ie ae i: Reeercee 51:23 
Cee 90: SAL plas vee 
=p protoxide ......... oes. yp) eee 2-60 
Manganese............... Tee ie hs ata 34 
Lime ....... BOS ciccacs SRE SES + 
Mis <2... oe Be hc ocnaeaae 
a eRe ie PE. caine 693...» 693 
. hg eae ow 1-2 
99-25 
The above corresponds to 2 (JRO, } R,0) 3 SiO, + H,0. 
id 
