MINERALOGICAL NOTES — ANDERSON. 



279 



Girofla Mine, Chillagoe, Queensland. 

 (Plate lxxx., figs. 4, 5.) 



This occurrence is represented in the Museum Collection by an 

 exceedingly fine specimen of crystallised azurite associated with 

 malachite and chalcocite. The azurite is of two generations, the 

 earlier consisting of long prismatic crystals (to 10 x 2 - 5 x l - 5cm.) 

 of a deep velvety-blue colour and almost iridescent. The azurite 

 is partly changed to malachite, which forms embedded patches of 

 a vivid green ; the later generation of smaller, better developed 

 crystals implanted on the older azurite and in cavities is unaltered 

 and well adapted for goniometric determination. The whole 

 forms an extremely beautiful object. 



Four crystals were measured ; they are tabular on /x (105) and 

 elongated parallel to the b axis. The largest faces are those of 

 a (100), m(110) and /x ; the base and the orthodome faces are 

 strongly striated, as shown in the figures, and their signals over- 

 lap slightly. The following combinations were observed (iv. is 

 figured). 



