Chap. XL. ] vizagapatam : ramabhadrapur 
1105 
often showing lithoniargic impurities, and sometinies uU and soft black ; 
with also a little deep bluish-black pyrolusite. 
Sample A. 25. (Mamidipilli) taken from some 180 tons of stacked 
ore, consisted of various sorts of psilomelane, more or less compact, a 
good proportion of the pieces containing abundant orange-red spandite 
crystals. Several pieces contained ochreous clay and other impurities 
(lithomargic and quartzose). 
Sample A. 26. (Bankuruvalsa) taken from some 70 tons of stacked 
ore. More than half the sample was compact fine-grained pyrolusite, 
often in concretionary forms and frequently streakily mixed with psilo- 
melane. The remainder was psilomelane, both massive and concretion- 
ary. A smaller amount of lithomargic impurities than in the two 
preceding samples. 
These three samples were analysed by Messrs. J. and H. S. Pattinson 
with the following results : — 
Sonpuram. 
Mamidipilli. 
Bankuruvalsa. 
Sample No. A. 24. 
Sample No. A. 25. 
Sample No. A. 26. 
Manganese peroxide 
60-84 
47-71 
71-64 
Manganese protoxide 
2-68 
2-66 
2-19 
Ferric oxide 
19-42 
21-71 
13-00 
Baryta 
1-72 
1-22 
0-56 
Silica (combined) . 
2-90 
7-70 
2-00 
Silica (free) . 
0-50 
2-60 
2-50 
Phosphoric oxide . 
0-46 
1-105 
1-06 
Water (combined) . 
610 
6-20 
3-90 
Moisture at 100° C. 
0-70 
1-35 
0-60 
These are equivalent to : — 
Manganese . 
40-54 
32-21 
46-98 
Iron .... 
1360 
15-20 
9-10 
Silica (total) . 
3 '40 
10-30 
4-50 
Phosphorus . 
0-200 
0-482 
0-461 
From this it is seen that the Sonpuram and Bankuruvalsa samples 
just ccme within the limits for manganese-ores proper (see page 499), 
whilst the Mamidipilli sample must be described as ferruginous mang- 
anese-ore. 
