CiiAP. XXXII.] 
BALAGIIAT : JAMRAPANI. 
703 
the outlet from the Thirori lake, it partly consists of a coarse quartz- 
spessartitc-rhodonite-rock (rhodonite-gondite) like that found in the 
Kanithi Lady Pit at Chargaon, Nagpur district (see page 883). 
The outcrop along the ridge of this hill is very pronounced, and 
. „ dips taken at various points ranged between 25° 
Thirori South Hill. , . . ^ „ 
and 50 m directions between W. 30" N. and 
W. 5° S. The top of the hill is about 260 feet above the rice fields to the 
south. The ore in usually the hard grey variety, often interbanded 
with quartzite. Sample No. 49 was taken from the outcrop along the 
ridge of the hill and from the north base and consisted largely of the 
hard grey braunite-psilomelane mixture ; but some pieces were entirely of 
compact psilomelane, and some were composed of the lead-like variety 
of psilomelane containing black powder in cavities. The analysis (see 
page 704) indicates a mixture of 38 per cent, braunite, 60 per cent, 
psilomelane and 2 per cent, quartz. 
^ The small hillocks forming the southern arm of the ore-belt consist 
, . largely of the speckled variety of manganese-ore, 
^ ^" ' and to the east of Jamrapani nala the single ore- 
band runs north-east along what is marked on the map as a single 
ridge, but is really a series of hillocks and small hills. Further north 
there are probably 3 bands as shown. The ore-bands along this mass 
of hillocks and low hills consist partly of hard grey and speckled ore and 
partly of spessartite-quartzite. But as everything here is much obscured 
by jungle, it is not possible to give any details as to width, etc. Sample 
No. 53 was taken all along the Jamrapani hillocks and hills, wherever 
the outcrop consisted of apparently merchantable ore. It consisted 
partly of the speckled ore, partly of psilomelane, and partly of the 
fine-grained braunite-psilomelane mixture. A few pieces contained a little 
of the bronze-coloured mica (?) The analysis (see page 704) indicates 
a proportion of 31 per cent, of braunite to 69 per cent, psilomelane. 
At one point on the ridge due east of the village the ore-band is partly 
cut oS by quartz-muscovite-pegmatite iniected on 
Martite ard fuchsite. y t . mi,- . ■ 
to the line oi strike, inis pegmatite contains a 
large quantity of octahedral crystals up to an inch across of what must 
be regarded as martite, since the powder of the mineral is usually reddish 
brown and only slightly magnetic. Some pieces, however, give a black 
streak and are strongly magnetic and these must be regarded as 
the original magnetite that by alteration has given rise to martite. A 
little further along the outcrop this pegmatite becomes more quartzose, 
