160 THE MINERALS OF TASMANIA. 



Ben Lomond ; Dilston ; Beaconsfield ; Karoola ; George 

 Town; Heazlewood; Blue Tier; Inglis River; Gad's Hill; 

 and other places. 



295. SiciLioPHiTE (Silicified Serpentine). 



This peculiar altered substance is extremely variable in 

 colour, and occasionally almost opalescent. 



Near to the Long Tunnel Mine, Castray River. 



296. SiDERiTE (Carbonate of Iron). 



Occurs of sub-crystalline structure and pale-brown 

 colour, with quartz, both of which often contain gold, 

 Specimen Reef Mine, Brown's Plain ; in translucent masses 

 of a vitreous appearance, rapidly weathering brown ; also 

 abundantly in the opaque form, but rarely in well-formed 

 crystals, Mt. Bischoff ; in veins, usually of lenticular 

 form and often containing gold. Brown's Plain, Lucy 

 River, Rocky River, and other places in the vicinity of the 

 Pieman. This mineral appears to be the principal aurifer- 

 ous matrix of the locality ; on the surface it is usually 

 decomposed to the oxide. Abundant near the River Forth 

 in compact masses : at Port Sorell it is found intermixed 

 with quartz; in great profusion at Zeehan, Dundas, and 

 Heazlewood, where it forms the common lode gangue of 

 the silver-lead mines. The crystals are rarely obtained, 

 still at the lastmentioned field they are occasionally met 

 with, but small in size. It is more often found in the lode 

 cavities in semi-lenticular forms aggregated together. In 

 the Heazlewood silver-lead and adjacent mines it is com- 

 monly coloured pale-green by the admixture of the oxide 

 of chrome. 



" In the adits driven outside the main tin deposit of 

 Mount Bischoff there occur druses of fine quartz crystals, 

 amongst which generally appear brown saddle-shaped 

 rhombohedra and aggregations of rhombohedra of this 

 material. In places it occurs also massive, of a deep brown 

 to nearly black colour " (Ulrich). 



297. SiEGENiTE (Sulphide of Cobalt and Nickel). 



Occurs massive, of a steel-grey colour, intermixed with 

 magnetite, pyritte, and niccolite. Rocky River Mine. 



298. SiLLMANiTE ( AnJiydrous Silicate of Aluminium). 



Occurs in the form of sillmanite-schist at the Lucy 

 River, a tributary of the Pieman, and at Mt. Stewart 

 Heazlewood district. 



