3*2 THE MINERALS OF TASMANIA. 



sulphide. The bright well-developed orthorhombic crys- 

 tals gave the following result upon analysis: — 



Per cent. 



S = 13 62 



Sb = 28-68 



Pb = 42-39 



Cu = 11-93 



Fe = 1-97 



98-40 



56. Braunite ( SiJicomanganate of Manganese). 



A dark brownish-black to steel-grey mineral, with the 

 streak the same colour. Hardness, 6" 65. Specific gravity, 

 4" 75. Occurs abundantly at the West Comet Mine, Dun- 

 das. 



57. Bronzite. (See Enstatite.) 



58. Breithauptite ( Antimonite of yickel ). 



This substance has a distinctly copper-red colouration 

 and crystallises in the hexagonal system. 

 Analysis by Mr. W . F. Ward : — 



Per cent. 

 Ni = 34 

 As = 23 

 Sb = 37 



It does not appear to be plentiful. 

 Locality : Central Balstrup Section, Zeehan. 



59. Brookite (TiUinic Oxide). 



This species is of the same composition as the more 

 abundant rutile, but crystallises in the orthorhombic 

 system. It occurs with it and anatase at Clayton's Rivu- 

 let, also near the Pieman River and at Back Creek, near 

 Lefroy. At the last locality it is found in flaky pieces^ 

 which are blood-red in colour by transmitted light. 



60. Brucite (Hydrated Magnesium Oxide). 



The common form of this mineral is massive and 

 foliated with a somewhat pearly lustre. It is invariably 

 found in or near serpentine. Occurs in large masses at 

 the Heazlewood ; in hexagonal plates which are embedded 

 in serpentine, Lower Castray River; common, west of 



