hillebband.1 NOTES ON TELLURIDES FROM CALIFORNIA. 
61 
other claims under the name Melones mine, showed plainly a nickel tellu- 
ride of reddish- white cast, of color like that of bismuth, 1 thickly scattered 
in grains, and showing pronounced cleavage and a brilliant luster. A 
concentrate was prepared by the aid of cadmium-boro-tungstate solution, 
and this was then laboriously hand picked by the aid of a powerful 
glass. There was certainly more than one foreign mineral present, but 
identification was not possible except as to a little gold and petzite. 
The chief impurity was a silver mineral, presumably hessite. If so, the 
analyses seem to indicate also native tellurium. A perfectly pure 
article could not be extracted because of difficulty in sometimes distin- 
guishing the foreign minerals from the one sought, but it was hoped 
that an analysis of both the selected and rejected portions would 
permit of calculating the composition of the nickel mineral with con- 
siderable certainty on the reasonable assumption that no impurity had 
been removed in relative excess over the other or others. 
The analyses below represent the composition of (a) the rejected, (b) 
the original, and (c) the selected material. Analysis b is given chiefly 
because of the cobalt determination, the nickel being probably a little 
high. Although but 0.22 and 0.13 grams, respectively, were available 
for the analyses a and c the data are believed to be more trustworthy 
on the whole than those of b, hence the figures under d have been 
obtained by calculation based on c and a only, after reducing them to 
100. Under e is shown the theoretical composition of NiTe 2 . Small 
amounts of iron, traces of copper, and perhaps one or two other 
elements are omitted, besides the three-fourths to 2 per cent of gold and 
petzite that remained unattacked by cold dilute nitric acid, in which the 
nickel mineral is readily soluble. 
The specific gravity of b at 22.5 was 7.72, which is probably higher 
than the true density of the pure nickel telluride. 
Analyses of melonite. 
a b 
c 
d 
NiTe 2 . 
Te 
75. 29 77. 72 
1 17.16 ) 
} 15 - 71 .10} 
8. 44 5. 09 
80.75 
18/31 
.86 
81.40 
18.60 
81.29 
18.71 
Ni 
Co 
Ag 
99.44 100.07 
99.92 
100. 00 
100. 00 
1 Under a lens, and to the unaided eye in certain lights, the color appears more hronze yellow. 
