Cu.vi-. XXXVI.] 
NAGPUR : MANDEI. 
937 
invariably soil the fingers. There is also a certain proportion of good 
hard grey ore. A sample was taken of some 1,G80 tons of ore stacked at 
this deposit in February 11)04. 
Such a large proportion of the pieces, however, contained yellow 
An experiment in spessartite that I thought it would be interesting 
cleaning. make an experiment on the cleaning of the ores. 
The sample was consequently coned and quartered twice, and one 
quarter, weighing 58 lbs., of the original sample was set aside as sample 
No. 31. I then cleaned one half of the original sample, forming sample 
No. 32, weighing 57 lbs., of the cleaned ore ; and sample No. 33, weighing 
38 lbs., composed of the portions of ore rejected, these being mostly very 
garnetiferous pieces. Complete analyses of these three samples were 
made at the Imperial Institute with the following results :l — 
Sample 
Sample 
Sample 
31. 
32. 
33. 
Manganese peroxide , . . . . . j 
54 -GO 
56-64 
48-65 
Manganese protoxide. . . . . . j 
21o5 
19-70 
21-95 
Ferric oxide ....... 
10-79 
9-73 
9-58 
Alumina ........ 
1-81 
2 17 
3-80 
Baryta ........ 
0-55 
0-71 
0-62 
Lime ........ 
0-83 
0-95 
1-70 
Magnesia ........ 
0-45 
0-38 
0-40 
Silica (combined) ...... 
5-09 
4-25 
5-48 
Silica (free) ....... 
0-67 
1-35 
3-35 
Phosphoric oxide ...... 
0-18 
0-20 
0-26 
Arsenic oxide ....... 
0 004 
0-005 
0-022 
Water (combined) ...... 
2 -.55 
3-01 
2-71 
Moisture at 100° C 
0-69 
0-49 
1-10 
Carbon dioxide ...... 
Oil 
015 
0-12 
Total 
99-874 
99-735 
99-742 
Manganese ....... 
51-2(5 
51-11 
47-80 
Iron ........ 
7 -.55 
6-81 
6-71 
Silica 
5-78 
5-60 
8-83 
Phosphorus ....... 
0-078 
0-087 
0113 
Moisture ........ 
0-69 
0-49 
1-10 
On studying these figures it is seen that thpre is a decided difference 
between the original sample 31 and the rejected material 33, the latter 
showing an increase in the amounts of silica and phosphorus and a decrease 
1 The following additional constituents were subsequently determined : — 
31 
32 
33 
NiO, C03O4, CuO 
Trace 
0-005 
Trace 
K2O 
0-34 
0-26 
0-21 
NagO 
0-25 
0-19 
0-25 
