CiiAP. XXXV.] 
JABALPUR : GHOGRA. 
825 
are now soft and decomposed. This ore, although apparently non- 
manganiferous, contains r70% of manganese, as shown by the analysis 
given on page 810. 
12. Ghogra and 13. Dhanwahi. 
See Bose, pages 75, 87, for Ghogra, and pages 75, 77, 84, 87, for 
Dhanwahi. 
The best account of the manganiferous iron-ores of this area, lying 
on the southern side of the Lora range, is the one by Mallet. According 
to himi : — 
' The hill half a mile north of Gogra is formed mainly of jasper-hematite. 
Near the base of southern slope there are a number of shallow ore pits2, but 
they arc only in talus, not in the rock in situ. The miners seek for the small bit * 
of ore which can be used at once in the furnaces, and leave the large lumps, which 
would require the labour of breaking up. The ore is a manganiferous micaceous 
hematite, containing a varying proportion of intorbanded jaspery quartz. It is a 
siliceous ore, although not very highly so. As the manganiferous band is entirely 
concealed beneath the talus, no estimate can be made of its thickness. Judging, 
however, from the large amount of debris, it seems probable that the thickness is 
considerable. As the loose ore must either lie directly over that in situ, or else have 
come down hill, and as the pits extend 20 or 30 feet (vertically) from the base of 
the hill, probably a large amoixnt of ore is obtainable by dry open workings 
whether these be through a deep mass of talus or into solid rock. 
' The proportion of manganese varies much, as can be seen from the outward 
appearance of the ore. In some specimens of the micaceous iron, the presence of 
manganese is scarcely apparent to the eye ; in others, the ore shows by its dark 
colour that it contains a large amount, and in the highly manganiferous portions 
psilomelane occurs in irregular segregations. A carefully chosen average sample, 
mac'e up of a large number of small pieces taken from different pits, yielded — 
Ferric oxide. ...... 66-33^Iron •IG-iS 
("Manganese (with traces of cobalt), 
t Oxygen . 
Phosphoric oxide . 
Sulphuric acid 
Sulphur 
Ignited insoluble residue 
Lime, alumina, water and undetermined 
66-33- 
12 -26 
6-83 
•27 
•03 
trace 
9-55 
4-76 
100 00 {sic) 
' The manganese exists, in large part at least, in the form of psilomelane, 
occurring in irregular segregations, or more minutely disseminated through the 
rock.' 
1 Fee. G. S. I; XVI, p. 101, (1883). 
2 ' Those to the west belong to the village Gogra, and those to the east to Danwai. 
