1»24 
MA>-GANESE DEPOSITS OF INDIA : DESCHIPTIVE. [PaHT TV 
wall-rock is a soft felspathic mica-schist or very schistose micaceous 
gneiss,''similar to that seen at Beldongri, and includes some layers of a 
pale green soapy schist that may be talcose. The north wall at this 
time showed a friable mica-quartz-schist, which may only be another of 
the layers so abundant in the ore-body, or may actually form the north 
wall of the quarry. 
Resting on the ore-body there is an overburden of 3 to 5 feet of allu- 
vial clay, containing scattered grains of mano-anese- 
ore and quartzite, and this is separated from the 
ore-body by a variable thickness of manganese -ore, gravel, and detritus. 
Near the east end of the quarry I found an exposure of rocks of 
Blanfordite. braiinite- extraordinary interest. One of these is a coarsely 
and albite. crystalline, white albite-rock containing scattered 
crystals up to one inch long, and dense aggregates, of a brown altered 
form of the mineral I have called blanfordite (see page 125). This 
rock passed into one made of finely granular braunite with 
abundance of fresh blanfordite of crimson colour, up to ^ inch long. 
In places the rock might be called blanfordite-rock : thin sections of it 
show interstitial apatite and a certain amount of a monoclinic 
amphibole with pleochroism as beautiful as that of the blanfordite ; this 
1 have called juddite (see page 159). 
Another type is a felspar-rock containing both aggregated and iso- 
lated crystals of braunite. Some of these are octahedra up to \\ to 
2 inches in diameter, and are often twinned on (101), as explained 
on page 58, to form either butterfly or interpenetration twins. Others 
are barrel-shaped crystals showing both the tetragonal and di-tetragonal 
pyramid. They are mostly doubly terminated and are sometimes twin- 
ned on (101). The strike of the braunite-albite-rock seemed to be about 
E. 20° S. It was impossible to see if this rock were an intrusive in the ore 
body, as seemed more probable, or if it were interbedded with the ore- 
layers. In the latter case it would be necessary to suppose a local flexure 
in the strike of the ore-body, which is at this end of the quarry about 
E. 10° N. The amount of this rock exposed is small and might have 
been overlooked, had I not first found the blanfordite-braunite rock on 
one of the ore-stacks. The coolies were able to show whence they had 
quarried the ore in this stack, for it had just been rejected by the con- 
tractor for containing too much ' silica,' as all visible impurity is de- 
signated by many of the contractors. 
On my second visit in December 1906, the rock carrying the braunite 
and blanfordite crystals was much better exposed, and seemed to be 
arranged parallel to the strike of the other rocks ; it is hence probably 
an intrusive parallel to the bedding planes. Many of the braunite crys- 
tals obtained were of large size, up to 3 ot 4 inches across, and showed 
all the faces noticed on the Lohdongri crystals (see page 917). 
