ECONOMIC GEOLOGY. 205 



The small beds of grey or creamy white crystalline limestone 

 near Tallur (p. 127) were insufficiently exposed to judge of their 

 real value. It might be worth somebody's while to remove the 

 surrounding soil sufficiently to ascertain their true size and possible 

 worth, for they are only about 3^ miles south-west of Toranagal 

 station on the Bellary-Gadag branch of the South Mahratta Railway. 

 The small bed of highly crystalline limestone exposed between 

 two trap flows near the ruined village of Hattigenhalli, about 2| 

 miles south-south-west of Toranagal, would appear too small in extent 

 to be worth looking after. 



Lime for building purposes is procured in very many places 



from sub-serial or alluvial formations of kankar 

 Lime-burning. 



or nodular limestone which are very commonly 



met with near to or on the surface of the hornblendic and other basic 



rocks occurring so largely in the Dharwar system as flows and dykes. 



No true slates useable for roofing or flagging purposes were met 

 Slates. with anywhere in the Bellary district. 



Some of the paler argillite schists and clayey traps weather on a 



large scale into soft semi-ochreous masses which 

 Mineral pigments. . 



are very suitable for pigments, and are used to 



some extent in the districts as colour-washes for house painting; 



these are derived from the Dharwar series. The commoner colours 



are dull orange and drab, but purplish grey and lilac are met with, 



and red tints ranging from pale pinkish to deep red in the softer 



haematitic beds are met with. The most of these were seen on the 



flanks of the western or Ramandrug section of the Sandur hills (see 



page 193). A great show of rich red ochre occurs on a low hill 



west of Chiggateru in Harappanahalli taluq. 



Clays for common pottery and brick-making are found abund- 

 antly in the river alluvia, but no high-class clays, much less pure 

 kaolin, were found in the older rocks in workable quantity. 



The mottled white and red argillite occurring close to the well 

 known temple of Kumaraswami, south of Sandur, has been referred 

 to by Captain Newbold as a kaolin available for high class pottery. 



( 2C5 ) 



