216 MANGANESE DEPOSITS OF INDIA ; MINERALOGY. [ PaRT I: 
a tew localities, e.g., at Ramdongri in the Nagpur district, on the neck 
joining hills 5 and 12. Magnetite-quartz-rock is also found at Katangjheri 
1 (Balaghat district) and at Sitapathiir (Bhandara district), the occur- 
rence at the latter locaUty being in the form of magnetite in quartz 
resembling vein-quartz. In none of these cases is the magnetite-bearing 
rock foimd in any considerable quantity. In some of the Vizaga- 
patam manganese-ore deposits a very magnetic mineral is often fovmd ; but 
in the few cases in which this has been tested it has been found to react 
slightly for manganese. Hence the mineral has been noticed under the 
heading of manganmagnetite. 
At Jamrapani, Balaghat district, there is a rock associated with the 
Jlarfte manganese-ore deposit in such a way as to suggest 
that it is an intrusive. It is composed of quartz, 
muscovite, and a black mineral, which has the outward shape of magnetite. 
Some of the crystals when tested give a black streak and are found to 
be magnetic ; these can be regarded as magnetite. Others give a red 
streak and are less strongly magnetic ; these are to be regarded as 
martite formed by the conversion, more or less complete, of magnetite 
into hematite. That the change has not been completed is shown by the 
magnetism that the mineral still retains. Other examples of martite 
have bepn found, as for example at Hatora, where there is a rock 
composed of magnetite, quartz, and some apatite and garnet, in which 
some of the magnetite seems to have been converted into martite, as 
evidenced by the streak. 
As I have already noticed, ^ the oxides of aluminium, iron, and 
. manganese, behave in laterite in a maimer exactly 
parallel with their behaviour in the laboratory. 
Thus the oxides of aluminium and iron, which are precipitated in the 
same group in the ordinary qualitative separation, are often very intimately 
associated with one another in laterites, although they also in many cases 
separate or segregate from each other. With manganese, however, there 
seems to be a very strong tendency to segregate from the other oxides with 
the formation of definite manganese-ores, containing of course a certain 
amount of oxides of iron and aluminium, more of the iron than of the 
aluminium. These ores usually take the form of nodules, masses, and 
veinlets. They are almost always associated with the ferruginous 
laterites rather than with the aluminoas laterites or bauxites. This is 
of course due to the greater chemical resemblance of manganese to iron 
than to aluminium. I have, however, noted one case in which an 
1 Rcc. 0. S. I., XXXIV, p. 168, (1906). 
