136 THE MINERALS OF TASMANIA. 



240. Phillips ITE (Hydrated Silicate of Aluminium, Cal- 



cium, and Potassium). 



This mineral is a common zeolite, which occurs in many- 

 basaltic rocks. It crystallises in the monoclinic system, 

 commonly occurring as twin and compound crystals. 

 Near the bridge crossing the Hellyer River it is very 

 plentiful in the vesicles of the basalt ; at Springfield with 

 other zeolites ; at Sheffield and in the vicinity of Bell 

 Mount it is equally profuse. 



241. Phlogopite (Fluosilicate of Potassium, Magnesiuniy 



amd Aluminium). 



This species is also known as magnesia mica. It crystal- 

 lises in the monoclinic system, with the habit of forming 

 oblong six-sided prisms, which are more or less tapering. 

 It occurs sparingly in granite at the Upper Emu River, 

 near the Hampshire Hills. It also occurs on mineral sec- 

 tion No. 5367-93m, in hornstone, associated with very large 

 bodies of magnetite and zinc-blende. It is found in large 

 hexagonal crystals with a perfect micaceous cleavage. 

 The colour is bright-green, varying sometimes to greyish- 

 brown. 



Locality : Near Mt. Heemskirk. 



242. Pholerite (Hydrated Silicate of Aluminium). 



This is a soft friable substance with a submetallic, 

 almost pearly, lustre, and scaly structure. It is so soft as 

 to be friable between the fingers. It occurs at Mt. Bischoff ; 

 North Heemskirk, and at the South Curtin-Davis Mine at 

 Dundas. 



243 Phosgenite (Chloro carbonate of Lead). 



The chemical formula of this distinct species is written 

 PbCl, PbCo3. 

 It crystallises in the tetragonal system, and has a 

 striking prismatic habit. It is highly adamantine, 

 with a pale to pure white colouration, and is usually 

 translucent. It has been found in the old slags of 

 Laurion, Greece, where the essential chlorine has been 

 supplied by the sea-water of the locality. In general, it 

 may be assumed that the chlorine is derived from 

 adjacent rocks, or with still more probability, by surface 

 waters carrying a small percentage of chlorides. The lead 

 is provided by the alteration of galena, to which the crys- 



