CuAP. XXV.] 
FEUUO-MANGANESE VALUES. 
539 
that is after the metallic manganese has been separated from its accom- 
panying constituents in the same way as the gold has been separated 
from its gangue. 
Of course, all the Indian manganese-ore is not converted into ferro- 
manganese ; but as it is not possible for me to say what proportion of it 
is converted into spiegeleisen, and what proportion is used in other ways ; 
and as it all could be converted into ferro-manganese we shall obtain the 
best idea of the potential value of the Indian manganese-ore, by supposing 
it all to be converted into ferro-manganese. In table 85 I give the 
weekly prices quoted in the Enqineerinq and 
Prices of ferro-manganese. . r i /• -vt it- i ^ ^ 
Mining Journal of New York from 1901 to 
1907 ; the volumes of this journal for years previous to 1902 are not 
in the library of the Geological Survey of India, and so I cannot 
give the quotations previous to 1901. From the table it will be seen 
that the quotations vary between $41 in May 1904, and $150 in 
February 1906, with a mean for the whole period of $61 '39^ It will 
be noticed on comparing this table with table 27 on page 415 showing 
the variations in the price of manganese-ore from 1900 to 1907, 
that the price of ferro-manganese varies more or less in sympathy with 
that of manganese-ore, though the two are not strictly proportional. 
Hence as the prices for manganese-ore were on the average 
higher during the years 1892 to 1900 than in the succeeding years, we 
should probably not be over-estimating the average price of ferro- 
manganese during these years if we applied the same average as for 
the 7 years 1901 to 1907. But to be quite sure of not over-estimating 
let us take $50, or, say, £10 or Rs.l50, as the average price per ton during 
the years before 1901. In table 86 I give (1) the annual totals for 
Indian manganese-ore production, (2) the number of tons of ferro- 
manganese they would give on the assumption that two tons of 
Indian manganese-ore would be required for the production of 1 ton of 
80% ferro-manganese (allowing for a loss of 20% of the manganese in 
the smelting), (3) the average price of ferro-manganese per ton assumed 
for each year, and, finally, (4) the total value of the Indian ferro man- 
ganese that could have been manufactured from the Indian manganese- 
ore produced each year. The fact that some of the Indian ore would not 
give as high grade ferro-manganese as 80% is more than neutralized 
by the fact that I have probably underestimated the price of ferro- 
manganese for the years previous to 1901. 
1 In December 1905 one car-lot was sold for $175. 
Ill I 2 
