708 GREAT SERPENTINE BKLT OF NEW SOUTH WALES, Hi., 



posed of crystals of felspar, and grains of quartz, in a fine-grained 

 ground-mass, greatly sheared and decomposed. Some tuffaceous 

 rocks, like M.B., 243, are fine-grained, black, aphanitic, and non- 

 schistose; and consist of fragments of felspar, quartz, spilite, and 

 felsite in a very fine-grained ground-mass. Here and there, lenses 

 of white, saccharoidal marble or limestone occur, usually fairly 

 pure, but sometimes containing a considerable amount of siliceous 

 material in parallel planes of bedding. 



The most notable rocks are the jaspers, which occur parallel to 

 the serpentine-belt, all along its length. In several localities, 

 radiolarian casts have been found in them, viz., at Woods' Reef and 

 Bingara, by Messrs. David and Pittman; at Nundle, the Namoi 

 River, and near Warialda by the present writer. The radiolaria 

 occur as chalcedonic casts in a siliceous matrix coloured by ex- 

 tremely finely divided particles of haematite. Frequently, the rock 

 is seamed with small veins of chalcedony, and considerably brec- 

 ciated, radiolarian, and non-radiolarian fragments being pressed 

 together in a most irregular fashion [e.g., N.T., 101, from near 

 Bowling Alley Point]. In places, the jasper-like rocks are banded ; 

 for instance, in Gulf Creek, about one mile below the mine, the 

 rock is a yellow and red, banded chert, which proves to consist 

 entirely of radiolarian remains, the faint outlines of the oval 

 patches being just visible. Except for the red colour and the 

 absence of finely divided epidote, etc., this rock is identical with the 

 crushed, radiolarian cherts of Bowling Alley Point. 



Here and there along the serpentine-line, now east, now west of 

 the intrusion, are peculiar rocks full of holes, which are clearly 

 due to the dissolving out of limestone-fragments. The insoluble 

 matrix of these, when non-schistose, appears to be identical with 

 the breccias of Tamworth and Bowling Alley Point ; and the whole 

 rock is more or less analogous to the limestone-bearing breccias of 

 Moonlight Hill, near Bowling Alley Point. If this be so, a definite 

 horizon is thus obtained, for the commencement of the study of the 

 stratigraphy of the eastern series. 



(2) The Tamworth Series consists of radiolarian claystones. 

 cherts, limestones, tuffs, and breccias, with coralline limestone 



