82 NOTKS ON TASMAMAN MINEHALS. 



crystals of remarkably high lustre. They were 

 of small size, pale green in colour, and almost 

 translucent. 



24 SiciLioPHiTE. — (Silicified serpentine.) 



This peculiar altered substance is extremely vari- 

 able in colour, and occasionally almost opalescent. 

 Near the Long Tunnel Mine, Castray River. 



25 Smectite. — [Hydrous basic aluminium silicate.) 



Obtained in patches of extreme softness almost 

 gelatinous, but soon becomes somewhat harder. 

 It has a metallic, almost silvery sheen. It 

 separates into folice of extreme tenuity. North 

 Lyell Mine, Mt. Lyell. 



26 Steargillite. — [Hydrous basic aluminium silicate.) 



A pale yellow to almost white substance with 

 strongly conchoidal fracture, and slightly 

 opalescent and smooth surface. Derby. 



27 Stephanite. — [Silver sulpkantimonite.) 



Brittle silver ore. It is black and dull in general 

 appearance, with a black streak. Found in thin 

 irregular patches, implanted on a silicious gangue 

 with "fire blende." Long Tunnel Mine, Castray 

 River. 



28 Stibicolite. — [Hydrous antimony dioxide.) 



In limited quantity as a pale yellow pulverulent 

 mass. British Zeehan Silver Lead Mine, Zeehan. 



29 Tourmaline. — [Boron aluminium iron silicate.) 

 The variety zeuxite, which is rich in iron and of 



an intensely dark green colour, occurs in remark- 

 ably large felted masses at the Castray River. 



30 WuRTZiTE. — [Hexagonal zinc sulphide.) 



A rare zinc mineral differing in crystallisation from 

 sphalerite. It is hemimorphic in habit, and by 

 that character it may be recognised when in 

 crystals. Usually it occurs in columnar masses. 

 Hercules Mine, Mt. Read, and Magnet Silver 

 Mine, Magnet. 



