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TRANSACTIONS OF THE [Nov. 27, 
November 27th, 1893. 
STATED MEETING. 
Progr. R. P. WHITFIELD in the chair, and twenty-seven persons 
present. 
SECTION OF GEOLOGY AND MINERALOGY. 
The following papers were read : 
ON ALLANITE CRYSTALS FROM FRANKLIN 
FURNACE, N. J. 
By A. 8. EAkie, CornELL UNIVERSITY. 
Much has been written concerning the widespread occurrence 
of allanite as a rock constituent, and many analyses have also 
been published. The present article deals entirely with the 
crystallography of the mineral, and is the result of an examina- 
tion of a large number of crystals coming from the Trotter 
Mine, Franklin Furnace, N. J. 
Allanite was first reported from this locality by C. T. Jack- 
son in 1850.* He gave a short description of its occurrence 
and an analysis, but nothing concerning the forms. His crystals 
came from a different locality, being in the feldspar of the old 
magnetite mines, while those described here occur with the zinc 
ores, in a great granite dyke.t The crystals are coal-black 
in color, very brittle, and occur in the common flat, tabulra 
forms, elongated in the direction of the ortho-axis. They 
contain many inclusions of the associated feldspar. The faces 
of the crystals are, in general, dull, and when magnified ap- 
pear to be much pitted, so that reflections with the Fuess goni- 
ometer are poor. Cleavage occurs parallel to the basal- and 
ortho-pinacoid faces and also in the direction of the prism face, 
but varying about 6°30’ from’ parallelism. An average of 
several readings gives an angle of 47°56’ between the ortho- 
pinacoid and this cleavage face. 
In all, fourteen forms occur on the crystals, none of them, 
however, being new. The forms are the following : 
* Allanite from Franklin Furnace, N. J., C. T. Jackson, Proc. A. A. A.S., 
1850, 323. 
+ J. F. Kemp—These transactions, Oct, 30, 1893. 
