■* 



496 



THE ORE-DEPOSITS OF BORAH CREEK, NEW 

 ENGLAND DISTRICT, N. S.W. 



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

 THE Society in Geology. 



(Plates xv.-xvi.) 



contents. page 



Introduction ' ... 496 



Geology 497 



Ore-Deposits ... ... ... ... ... ... ... 499 



The Fracture-System 500 



The Lodes 503 



The Genesis of THE Deposits 509 



Sequence of processes involved ... ... ... ... 513 



Correlation with other occurrences ... .„ ... 515 



Summary 516 



Conclusion 519 



introduction. 



In June and July, 1909, it was my good fortune to visit the 

 Conrad Stannite Mine at Borah Creek. The Manager, Mr. L. 

 Judell, made my stay a very pleasant one, and afforded me every 

 facility for investigating the mine throughout the greater part of 

 the workings. Unfortunately mining opei-ations were suspended 

 at the time of my visit; and though the water was being kept 

 out of the main drive, the bottom level was still under water and 

 could not be examined. It is my desire to record here my great 

 appreciation of Mr. Judell's kindness and help in assisting me to 

 an understanding of the mine and its workings. 



[The mine was again visited in May, 1910. It was then 

 under the management of Mr. Beasley, to whom, as well as to 

 Mr. J. F. Stephen, I am indebted for the information obtained 

 during this second visit.] 



The Conrad Stannite Mine is situated on Borah Creek, at 

 Howell, about 18 miles south by west from Inverell. It may be 



