Geology and Mineralogy. 73 
On the probable occurrence of Herderite in Maine ; by Wm. 
Eart Hippen. (Communicated in a letter dated Newark, New 
Jersey, December 11, 1883.)—To Mr. . Perry, of 
South Paris, Maine, an earnest and successful collector of Maine 
minerals, and the discoverer of many new mineral localities in his 
State, I am indebted for a few specimens of a dark, oil-green 
mica, having implanted on it clear crystals of a mineral resem- 
ling some varieties of apatite. he preliminary examination 
which I have made makes it probable that the mineral is the rare 
species Herderite.* The crystals are short, terminated prisms, 
general physical characters of the mineral. 
This mineral had been previously called topaz, from its resem- 
£ r 
herderite, so that there can be but little doubt of the correctness 
454, p. 546, Dana’s Syst. Min.) The planes observed are: 0(001), 
0), Z (110), 3-2 (302), 1% (011), 3-4 (031), 6-% (061), $ (522), 
). Of these planes all occur on herderite except 3-4, 3-4, #. 
53°; OA14=156° 40! for herderite=156° 59/; OA3=112° 40’ 
~~ herderite=112° 35'.—E. S. Dana.] 
ville A. Derby in a letter dated Rio Janeiro, October 30, 1883).— 
Probably, according to trials by Plattner and Turner, an anhydrous phosphate 
Prog and lime with fluorine, stbartiataibas with J. J=115°534,G. = 2985. 
dinger, Phil. Mag., IV, i, 1828. J. D. Dana’s System Min. p. 546. iS 
