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so preponderant as to constitute a manganese ore. These 

 ironstone outcrops may, in some cases, harbour copper ore at 

 a depth; especially is this likely in proximity to the marble 

 belt. 



Gmphite. — A belt of gritty and argillaceous meta-sedi- 

 mentary strata, several hundred yards in width, and situated 

 about a mile west of the Port Lincoln Mine, is charged with 

 graphite to such an extent as to offer possibilities for develop- 

 ment. Other outcrops of graphite-bearing rocks are reported 

 from the district. 



Clay. — A wonderful development of remarkably pure 

 kaolin occurs about 15 miles west of Tumby Bay, between 

 Chinmina Creek and Cockaleechie Creek. 



Felsfar. — A massive pegmatite dyke, with large blocks 

 of orthoclase felspar, cuts the marble series in the Mine 

 Creek, near the Port Lincoln Mine. This is an -example of 

 many similar felspar-bearing formations of economic value 

 developed in the district. 



Marjnesium Minerals. — Chrysotile (asbestic), talc, and 

 magnesite aro abundantly developed in the marble belt, and 

 cannot long remain unexploited. 



