Chap. XV.] 
GONBITE SERIES : ORIGIN'. 
31.5 
one would not expect were the gondite rocks of igneous origin, as there is 
no apparent reason why they should always have chosen rocka of original 
sedimentary origin into which to intrude themselves. For the quartzites 
and para-gneisses are not any less strong structurally than the hornblende- 
schists, ortho-gneisses and crystalline Hmestones. Moreover, why should 
the manganese-bearing rocks associated with the crystalUne limestones 
almost invariably contain piedmontite, with spessartite and rhodonite as 
a rule absent, or only present in small quantity ; whilst the manganese • 
bearing rocks associated with the mica-schists, quartzites, and para- 
gneisses, are characterized by the almost invariable absence of piedmon- 
tite and the frequent great abundance of spessartite and rhodonite ? The 
only explanation that seems to meet the case is that the manganese- 
bearing rocks were deposited as sediments with the rocks with which they 
are associated, so that they partake to a certain extent of the chemical 
composition of the enclosing rocks. 
Main conclusions as The conclusions that it seems legitimate to 
to origin. draw from the preceding paragraphs are : — 
(1) That the portions of the metamorphic and crystalline complex 
with which the manganese-bearing rocks of the gondite series 
are associated in the districts of Chhindwara, Xagpur, Bhan- 
dara, and Balaghat, are the more highly metamorphosed equi- 
valents of the rocks that have been designated the Chilpi 
Ghat series in the Balaghat district. 
(2) That the manganese-bearing rocks are not intnisive in these 
metamorphosed sediments, but have been formed by the 
metamorphism of manganese-bearing sediments deposited 
contemporaneously with the sands, clays, and impure grits, 
from which these quartzites, mica-schists, and gneisses, 
have been formed. 
It should be noticed that there is nothing in the mineral com- 
position of the rocks and ores of the gondite series that seems in the 
least repugnant to this theory that they are metamorphosed sediments. 
The question naturally arises as to the shape of the masses of water 
The shape of the in which the manganiferous sediments were 
areas of deposition. deposited. A reference to the map (Plate -13) of 
this area will show what a large number of outcrops of the rocks and ores 
of the gondite series have been found. It will also be seen that the form 
these outcrops assume is that of long bands. In a few cases these 
bands can be traced until they die out in lenticular fashion. As good 
