Records of the Geological Survey of India. 
[vol. VII. 
122 
Clay-slates occur both in the Kadapa and Karnul formations in Madras; but though 
thin slabs can be obtained, they are not suited for roofing purposes, and where harder and 
more durable stone is obtainable their employment for flagging is not recommended. 
References. 
Powell, Panj&b Products. 
Medlicott, N. W. Himalayas, Mem. Geol. Surv., India, III, p. 176. 
Hughes’ notes on the slates at Chilli, Kumaon, Records, Geol. Surv., India, III, p. 43. 
Blanford, Geology of Western India, Mem. Geol. Surv., India, VT, p. 217. 
King, Kadapa and Karndl formations, Mem. Geol. Surv., India, VIII, p. 281. 
Second note on the mateeiais foe iron manufacture in the Raniganj Coal-field, 
by Theodore W. H. Hughes, a. r. s. m., f. g. s., G-eologieal Survey of India. 
In continuation of my former paper* on the raw materials for iron smelting in the 
Raniganj field, I have a few analyses of iron ore and kunkur to record which will afford a 
more complete series for computing their values than already exists. 
Iron-ore .—The percentage of iron in several different samples of ore from various 
spots in the Raniganj field has been given in the Memoirs of the Geological Survey,f but 
the impurities were not separately estimated. In the following analyses the amount of 
alumina, lime, phosphoric acid, and insoluble residue, besides the iron, is indicated; and a 
useful comparison can be instituted between the Raniganj ores and those of other countries. 
All the samples are derived from the iron-stone measures, known geologically as the iron¬ 
stone shales group, and they were collected entirely in the western portion of the field :— 
Bagunia No. 1. 
Bagunia No. 2. 
Boldih. 
| Chalbalpur. 
Kulti. 
>3 
'o 
'C3 
*cd 
S 
Sibpfir. 
Remarks. 
Insoluble 
136 
10-6 
20'4 
14'8 
19-6 
18*8 
212 
(a). A little magnesia 
and sulphuric acid 
(Silica) 
(116) 
(8-6) 
(168) 
(121) 
(16-4) 
(16-2) 
(17-) 
occur in the Chal¬ 
balpur, Chin&kuri, and 
Sesquioxide of iron 
65-44 
53‘2 
52-28 
66-45 
60'4 
6292 
43*82 
Malakold ores. Being 
small,it was not quan- 
Protoxide of iron 
13-48 
1-08 
8-92 
titatively determined. 
Alumina 
625 
407 
6*89 
4-7 
6-8 
3'91 
5-17 
Lime... 
*8 
10 
4-03 
2-24 
2'9 
2*88 
336 
Magnesia 
•7 
*85 
1-8 
a 
-6 
a 
a 
Phosphoric acid... 
'71 
•57 
1*43 
2-05 
22 
2-57 
23 
Sulphuric acid ... 
'55 
... 
a 
a 
a 
Loss on ignition 
13'5 
160 
13-2 
9-6 
9-2 
10-2 
14*4 
Total 
101*0 
100-32 
100-15 
98'84 
100*7 
101-28 
99-17 
Metallic iron 
45-80 
4772 
37'43 
46-5 
42-28 
44-03 
37-60 
* Records, Geological Survey of India, 1874, Vol. VII, Pt. I, p. 20. 
f Memoirs, Geological Survey of India, 1860, Vol. Ill, Art. 1, p. 194. 
