MANGANESE DEPOSITS Ol' INDIA: ECONOMICS. [pART 111 ; 
higher than those given above for ores used for the iron and steel industry. 
This question I have discussed in the chapter on the uses of manganese, 
where (page 599) the prices will be found, as well as the points 
that have to be taken into account in valuing an ore for chemical pur- 
poses. 
It will be interesting to discuss the question of the nomenclature of 
Nomenclature of man- manganese-ores for commercial purposes, deal- 
ganese-ores and mangani- ing only with those used in the metallurgical 
ferous iron-ores. industry ; for these form by far the larger pro- 
portion of the whole. It is customary to divide the ores containing 
manganese into manganese-ores proper, and mangani ferous iron- 
ores. There is every gradation in composition between iron-ores 
practically free from manganese, through iron-ores containing larger 
and larger quantities of manganese, to manganese-ores containing 
large quantities of iron, and from these, through manganese-ores con- 
taining smaller and smaller quantities of iron, to manganese-ores 
practically free from this constituent. All these grades of ore are of 
use in the iron and steel industry. It is customary to divide them 
into iron-ores, manganiferous iron-ores, and manganese-ores. The diffi- 
culty is to decide what is the minimum percentage of manganese 
in an iron-ore that shall necessitate the prefixing of the adjective 
' manganiferous ', and what is the minimum percentage cf man- 
ganese that shall necessitate calling an ore ' manganese-ore ' instead 
of ' manganiferous iron-ore '. I understand that the least percentage 
of manganese in an iron-ore that is usually paid for is 8%. And it 
hardly seems necessary to call an iron-ore ' manganiferous iron-ore ' if 
it contain a smaller percentage of manganese than 5. It was formerly 
the custom in the United States to call an ore a manganiferous iron-ore 
if it contained less than 44% manganese (equivalent to 70% Mn02)- 
Later, ores with as little as 40% Mn have been termed manganese-ores, 
and those below this limit manganiferous iron-ores. According to this 
method one often sees an ore referred to as a manganiferous iron-ore 
that contains more manganese than iron. 
^^j^^enuginouM inanganese. rpj^-^ gggms to me to be irrational^ , and easily to 
be avoided by creating a class of ferruginous 
manganese-ores. Suppose the total of manganese plus iron in the ores of 
1 The conirnercial nomenclature arises from the buyers and sellers calling iiiaiujaneic- 
o;c all ore from which rich ferro-manganese alloys can be made, and mang .n jercw 
iron-ore such ores as are suitable for making low grade ferro-manganese, and spiegel- 
eisen. 
