66 
Proceedings of the Royal Society 
mountain chain of the interior die away. The cohalt ores of New 
Caledonia habitually contain veins of chrome ore, which appear to 
come from chrome ore contained in the subjacent serpentine. 
2. The Physical Condition of the Cobalt Ore. — The ore from the 
ferruginous masses containing cobalt is solid, round, and sometimes 
a little hard. I have here some specimens that show the appear- 
ance it presents on the ground. It resembles iron ore, rotten or 
scoriaceous, the cavities of which are filled with bluish-black cobalti- 
ferous manganese. 
3. The Chemical Composition of the Cobalt Ores , Sfc. — The 
average percentage of the ore, taken from a large number of 
analyses, runs about 3 to 5 per cent, oxide of cobalt, along 
with about 1^ per cent, of oxide of nickel. Besides these two 
oxides, the ore contains binoxide and protoxide of manganese, 
peroxide of iron, alumina, lime, magnesia, silica, chrome ore, and 
water. The following are the detailed analyses : — 
Mean. 
Oxide of cobalt, (5 ’ll) 
3-48 
3-41 
4-16 
5-56 
6-40 
7-76 
Oxide of nickel, (1 *46) 
1*05 
1-32 
1-64 
1-48 
1-64 
1-64 
Binoxide of manganese, 
23-34 
18-78 
22-37 
15-94 
28-20 
34T0 
Protoxide of manganese, 
2-12 
2-33 
0-82 
3-40 
4-90 
3-50 
Sesquioxide of iron, 
15-71 
14-39 
10-06 
16-06 
13-04 
8-91 
Alumina, 
21 -20 
31-73 
13-44 
10-30 
16-76 
14*29 
Lime, 
2-68 
1-95 
0-32 
1-53 
1-70 
1-59 
Sulphuric acid, 
0-42 
Magnesia, 
Silica and chrome ore, . 
2-16 
Trace 
0-70 
0-70 
6*79 
9-20 
1-81 
30-00 
23-00 
5-32 
2-20 
Combined water, 
17-84 
19-22 
j 17T9 
i 9*23 
12-14 
9-42 
Moisture, 
1-70 
4-63 
\ 12-86 
9-20 
15-80 
100-48 
99-99 
100-00 
100-06 
99-80 
100-00 
It will be seen from the analysis of the six samples of cobalt ore 
(and which are representative analysis of several hundred tons), 
that the composition of the ore varies very considerably, — the silica 
and chrome ore being as high as 30 per cent, in one representative 
sample, and as low as 1 81 per cent, in another. 
In the numerous samples submitted to analysis, I have not heard 
of copper, sulphur (either in free state or as a sulphide), or arsenic, 
being found in these ores of cobalt. 
It has not been found advisable to attempt to utilise as yet any 
portion of the constituent of these cobalt ores except the cobalt and 
