138 
In some pseudomorphs the hydrous iron oxides mentioned 
above are wanting, in others they are replaced by micaceous 
hematite, while the ægirine is always of the same acmite-like 
habit and fibrous structure. A fuller description has been given 
in another place!; here, the analysis of them is quoted to- 
gether with analyses of arfvedsonite and ægirine in order to 
show the general character of the alteration process. 
sø 
Arfvedsonite Arfvedsonite- Ægirine 
(Lorenzen) pseudomorphs (Lorenzen) 
(Detlefsen) 
SiO Ate N 43°85 44-19 49-04 
N or 4:45 463 1:80 
Hen Onn EEE ET 3°80 34°67 29°54 
Не Е. 33:43 1:16 4°82 
МПО: "45 "45 tr 
MeO peek ice: 81 18 tr. 
CaO eee ee 4:65 2:35 2:70 
Nas OPEN "ZE 815 11°61 13°31 
|. (Ce 1:06 13 tr. 
BRO sea eat 152 30 = 
100°80 99°67 101:21 
Эро. 344 357 3:63 
This alteration of the arfvedsonite no doubt belongs to 
the pneumatolytic phase; it is of special interest because it 
indicates the presence of an excess of oxygen during this 
phase. It is probable that the process is contemporaneous 
with, and partly due to the same agencies as, the conversion, 
mentioned above, of eudialyie into catapleiite; for in the spe- 
cimens where the arfvedsonite is highly altered the same holds 
good of the eudialyte too. 
Ainigmatite occurs in the sodalite-foyaite in varying but 
as a rule small amounts; it is in allotriomorphic anhedra. Mi- 
crographic intergrowths with arfvedsonite or ægirine are not 
uncommon. 
1 Meddelelser om Grenland XIV, p. 195 (1894). 
? Loss on ignition. 
