68 HUGHES : WARDHA VALLEY COAL-FIELD. 



the selection of sites for boring 1 purposes, the porosity of the sandstone is 

 one of considerable value. The estimated thickness of these rocks is 

 about 400 to 500 feet. They are extremely well exposed in the Wardha, 

 below the old pit at Ghugus. 



Above, come sandstones which are more typical of the group, and 

 accord with the description given by Mr. Blanford of the' sandstones 

 near the station of Kamthi. They are compact grits, breaking* with a 

 conchoidal fracture, and ringing under the hammer ; fine-grained or 

 coarse, friable or compact sandstones with red blotchy streaks upon a 

 whitish, yellow, or brownish-red ground ; compact argillaceous sand- 

 stones, deep red, buff, or pale-purple in color ; coarse, white or grey fels- 

 pathic sandstones ; and ferruginous sandstones. 



The shales are compact, argillaceous beds of various colours, red 



predominating-. They are very characteristic of 

 Shales. 



the series. 



The clays are usually red and green. A few beds are interstratified 

 with the lower sandstones, but the fullest develop- 

 ment of them is in the higher part of the series. 



The conglomerates and pebble beds form a very small proportion of 

 the Kamthis, and are seldom found with the lower sandstones. They 

 usually occur higher up in the series, accompanying the compact, vitreous 

 blotchy-colored sandstones. 



Extremely hard, vitreous bands of a few inches in thickness are met 

 with occasionally. They are not characteristic of any horizon, but more 

 accompany the lower sandstones than the upper ones. 



Ferruginous matter is very liberally distributed through the whole 



, „ of the Kamthi series, chiefly as a coloring" agent, 



Large percentage 01 ' J & & ' 



iron in some sandstones, ^ut locally it becomes concentrated, and many of 

 the sandstones contain a high percentage of iron : samples that were 

 submitted for analysis yielded from 17 to 35 per cent. Manganese 

 is occasionally a coloring medium, and some of the sandstones hold as 

 ( 68 ) 



