F. A. Genth’s Contributions to ; 
meykite—ca. The first observation of the occurrence of 
kite on Lake Superior was made by T. Sterry Hunt (this 
[2], xix, 417), who detected this mineral by its tin-white 
Color, and the results of his analyses in the peculiar mixture of 
; Pa and domeykite from the Michipicoton Island. 
D. Whitney (this Jour. [2], xxviii, 15), remarks that it appeared 
homogeneous in composition, of the general appearance of copper- 
nickel, forming nodules with a structure in concentric layers. 
Have in my collection two little pieces of it, the first re- 
ceived about two years ago from Prof. Whitney, and another 
t a short time ago from Prof, Brush. The latter, when received, 
da fresh fracture and showed distinctly the mechanical mix- 
ture of the copper-nickel with a tin-white mineral, which how 
ver, quickly tarnished. The other was quite homogeneous, 
When obtained, but of a paler color than copper-nickel. Now, 
having tarnished and become brown, while the copper-nickel still 
, Page its bright color and metallic lustre. The concentric struc- 
ure 7 
09 bs per-nickel, followed again by domeykite, which is sur- 
unde 
of a line in thickness. 7 
8. In the Portage Lake Mining Gazette, vol. ii, No. 9, of Sep- 
tember, 1860, an article appeared headed “A new mineral,” in 
Which it was stated that a large mass of vein rock with a great 
mat 
and @ little epidote. It is described as fine steel-grey, very 
ile like copper pyrites, of about the same hardness, and 
sisting of copper and arsenic, without any sulphur. Fro 
i Sona Prof. Brush for a very fine piece, which he lately 
_ —s784t from the same locality. 
| -, Massive, Hardness a fitde below that of fluor; sp. gr. at 16° 
C =7'750; color on a fresh fracture between tin-white and steel- 
-y) quickly tarnishing, first changing into yellowish and pinch- 
'*. ae rwards into beautiful pavonine and rainbow colors, at 
4. ‘Urning brown. Lustre metallic when fresh, dull after oxyd- 
‘tion, Fracture uneven, somewhat subconchoidal, ae 
; One of my specimens shows a thin coating of an arseniate o 
“per, probab: y olivenite. 
Ae Jour, Scr.—Szconp Serres, Vou. XXXIII, No. 98.—Marcu, 1862. 
25 , 
