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THE TIN-DEPOSITS OF NEW ENGLAND, N.S.W. 

 Part i. — The Elsmore-Tingha District. 



By Leo A. Cotton, B.A., B.Sc, Linnean Macleay Fellow of 

 THE Society in Geology. 



(Plates lix.-Ixiv.) 



CONTENTS. 



Chapter i. — Introduction, Geography, Topography ... 733 



Chapter ii. — Geology 737 



Age of the Rocks 738 



Silurian System 741 



Permian System 742 



Tertiary System 746 



Rocks of Undetermined Age .. ... 749 



Chapter iii. — The Tin-Ore Deposits 750 



Alluvial 750 



Deep Leads 750 



Vein-Formations 750 



Systems of Fractur 752 



Nature of Ore-Deposits 759 



Chapter iv. — Conclusion 779 



Chapter i. — Introduction. 



Tin-mining in New South Wales is chiefly carried on in the 

 New England District, which comprises the Northern Tableland. 

 There are two well defined tin-bearing areas, one having Emma- 

 ville as its centre, and the other embracing the country about 

 Tingha. These are separated by a barren tract consisting of a 

 series of slates and claystones largely covered by basalts. This 

 unprofitable zone is some 20 to 30 miles in width, and has been 

 worked for tin only in the neighbourhood of Wellingrove. Both 

 tin-bearing areas are associated with granite and allied rocks. 

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