12 GREAT SERPENTINE BELT OF NEW SOUTH WALES, iii., 



The coralline limestone has been described as being of a greyish- 

 blue character, near Bowling Alley Point. It is associated with 

 tuffs, and contains a considerable amount of foreign, insoluble 

 matter. In places, it has been entirely swamped by spilites and 

 breccias, and is represented by the occurrence of isolated frag- 

 ments of limestone, frequently fossiliferous, in these two pyrogenic 

 rocks. Southwards, on Folly Creek, white, crystalline limestone 

 occurs, containing bands of insoluble, siliceous material. North- 

 wards, on Black Jack, the rock is a pinkish, brecciated marble, with 

 much secondary calcite. Further north, white and pink crystal- 

 line limestone occurs, near Moonbi, but it is much altered by con- 

 tact with the granite. Altered limestones, again, occur at Car- 

 michael's farm, east of Tamworth. The crystalline limestones of 

 Tamworth are greyish in colour, and stretch northwards to 

 Attunga, where they are greatly altered by contact with the gran- 

 ite, in two localities. Further northwards, the limestones are 

 unaltered. The few specimens of this limestone that have been 

 analysed, all show a surprisingly small percentage of magnesia. 

 The following are the figures for some of these rocks, obtained 

 from Mr. Carne's "Copper Mining Industry in New South Wales," 



At Moonbi, Tamworth, and Attunga, where the limestone is 

 invaded by granite, some very interesting rocks occur. 



The Moonbi rocks form an intricate complex, and, as yet, have 

 been little studied. Besides the altered forms of the more or less 

 pure limestones, there are several rocks which probably originated 

 from calcareous shales. Of these, M.B., 172, and 173, are most 



