AZURITE CRYSTALS FROM MINERAL HILL. 275 



AZURITE CRYSTALS FROM MINERAL HILL, NEAR 

 CONDOBOLIN, NEW SOUTH WALES. 



By C. Anderson, m.a., d.sc, (Edin.) 



Mineralogist to the Australian Museum, Sydney. 



(Contribution from the Australian Museum.) 



With Plates V, VI. 



[Read before the Royal Society of N. 8. Wales, October 3, 1917.] 



Among recent additions to the mineral collection of the 

 Australian Museum are three hand specimens of beautifully 

 crystallised azurite from the Iodide Mine, Mineral Hill. A 

 number of the crystals have been measured on the gonio- 

 meter and the results are embodied in the present paper; 

 at the same time the elements of azurite are discussed in 

 the light of the angular measurements obtained and new 

 constants have been calculated from these angles. 

 Occurrence and Associated Minerals. 

 The Mineral Hill Silver Field has been described by Mr. 

 E. F. Pittman. 1 It is situated in Parish Talingaboolba, 

 Oo. Kennedy, about 42 miles north of Condobolin. The 

 ore-deposit occurs in gritty sandstones and slates, probably 

 of Devonian age. In the ore-body these rocks have been 

 metamorphosed into very hard, dense, siliceous rocks such 

 as quartzite and jasper, and the ore-body itself consists 

 essentially of friable, gossany material with interspersed 

 masses of quartzite, and containing such minerals as cerus- 

 site, azurite, cuprite, and cerargyrite. The workings have 

 not reached the unoxidised zone (the mine is now idle), but 

 Mr. Pittman concludes that these minerals will be found 

 to give place at a depth to argentiferous galena, associated 

 in places with chalcopyrite. 



1 Pittman, Ann. Kept. Dept. Mines N.8.W., 1912 (1W13), pp. 170- 172 



