E. 8S. Dana—Mineralogical Notes: Allanite. 479 
Art. LX.—Minerclogical Notes ; by E>warp S. DANA. 
1. ALLANITE. 
SOMEWHAT more than a year since, Professor James Hall 
Bleed in the hands of the writer a crystal of allanite for crys- 
tallographic description. This crystal was Haak from the 
tagnetite ore bed at Moriah, Essex County, New This 
locality has in time past afforded specimens of hie same min- 
eral and sometimes of very considerable size, but the erystal in 
question is remarkable for this locality and the species, both in 
lar in form, through the predomination of the orthopinacoid, 
and is in general rectangular in outline. It measures about 
3% by 44 inches; the planes are smooth, their intersection lines 
mostly sharply defined and the entire orystal is nearly perfect 
and symmetrical except where the surface is penetrated by 
magnetite. The habit of the crystal is shown in the’ adjoining 
figure,* which is one-fourth of the natural size. The eceurring 
planes are as follows: 
ii (100, a) —1-i (101, «) 
O (001, e) +1-i (101, r) 
T (110, J) 4+2-¢ (201, 0) 
i-2 (210, u) l-i (011, 0) 
—}-i (102, m) <1 1, @ 
+1 (11), 2) 
\ 
Allanite. 
The position here adopted is that of Kokscharof (Min. Rassl., 
iil, 844), and the letters are the same as his except those of the 
pinacoids and the unit prism: a=Z, c=M and /=z. For 
comparison it should be stated: that in the figures on p. 286, 
Dana’s System, 5th edition, 1-/ is the orthopinacoid, and 7-7 the 
basal pinacoid ts Kokscharof (a and ¢ respectively of the above 
figure); the position taken in Dana’s System is that of Mohs. 
The angles on this crystal could be measured dnly with the 
contact Ses errs and hence they are not sufficiently accurate 
to give a basis of comparison with those obtained in more 
favorable circumstances; they are consequently not quoted 
n general it may "be said that they i satisfactorily 
wit hae generally accepted for the species. 
figure was inserted. by mistake of the printer, in a paper by the present 
writer Stibnite in the number of the Journal for September, 1883 (IIT, xxvi, 
Pp. 
