124 THE MINERALS OF TASMANIA. 



Nephelite readily alters to some of the zeolite group of 

 minerals, such as thomsonite and analcite. It occurs as 

 micro crystals in the trachydolerite of Table Cape and 

 Circular Head ; plentiful as an essential in the nephelinite 

 of Shannon Tier ; fairly abundant in the solvsbergite 

 porphyry and hauyne-trachyte of Port Cygnet. 



22*2. NiccoLiTE (Arsenide of Nickel). 



The hexagonal crystals of this mineral are exception- 

 ally rare. Its common mode of occurrence is massive, 

 reniform, and sometimes columnar. It is also known from 

 its colour (it does not contain any copper) as copper nickel 

 and kupfernickel. 



It is an important ore of Ni, which is always of an 

 unusual copper-red colour. It contains empirically from 

 40 to 45 per cent, of Ni. 



It occurs in solid to vesicular masses at a locality about 

 10 miles from Leslie Junction, North-East Dundas. Not 

 infrequently it is partially coated with annabergite, 

 derived from its alteration. It has been obtained in small 

 quantity near Mt. Agnew, and at the Rocky River Mine it 

 has occurred in small particles disseminated in other nickel 

 minerals. " Occurs at Zeehan in the Austral Valley, near 

 the foot of Manganese Hill, on the old Central Balstrup 

 lease. The mineral is massive or forms reniform crusts in 

 a vein carrying galena and some antimonial lead ore in a 

 gangue of siderite. With it ruby silver ores may be 

 found." (L. K. Ward.) 



223. NiccocHROMiTE (Dichromate of Nickel? ). 



A yellow powdery substance accompanying zaratite on 

 chromite in serpentine from the Heazlewood. A yellow 

 incrustation, presumed to contain nickel, also occurs at 

 Trial Harbour. The identification is extremely doubtful, 

 but that the first mentioned substance contains Ni is 

 beyond doubt. 



224. NoNTRONiTE (Hydvated Silicate of Iron). 



This is a variety of chloropal, and is always amorphous. 

 It is of a dull greenish colour, with an unctuous feel, and 

 somewhat waxy lustre. It always has a conchoidal frac- 

 ture. Occurs near New Norfolk ; as veins in the magf- 

 netite at Hampshire ; and of a pale yellow-green colour 

 near Bell Mount, Middlesex. 



