174 the minerals of new south wales. 



Iron Pyrites. 



Cheni. comp.: FeS.,. Sulphur 53-3; iron 46*7 = 100. Crys- 

 tallizes in the cubical system. Occurs massive and crystallized, 

 the most common forms being the cube and the pentagonal 

 dodekahedron. "Well-formed cubes partially decomposed into brawn 

 haematite are common in many deposits with gold, and are known 

 to the miners by the name of " devil's dice." All specimens of 

 pyrites which I have examined have without exception contained 

 traces of gold, and in some cases large amounts. 



As is found to be the case in other parts of the world, this 

 mineral is almost universally diffused throughout the metalliferous 

 districts of the Colony, and is found in rocks of all ages. 



"Well-formed crystals are found in the Manilla and Namoi 

 Rivers. In the tin district of New England it is very common — 

 Bathurst district ; at Gulgong, well-formed pentagonal dodecahedra 

 are common in the auriferous quartz veins. Very abundant in the 

 Adelong reefs ; the Carcoar District ; at Kiandra, crystallized in 

 cubes with molybdenite. 



Marcasite. — Rhombic pyrites. Chem. comp. : Iron sulphide = 

 FeS 2 . Same as the former, of which it is an allotropic form. 



Fluted rhombic crystals occur with arsenical and common pyrites 

 (auriferous) to the south of Reedy Creek, Shoalhaven River ; also 

 at Carcoar, with galena and other minerals. 



Pyrrhotine. 



Magnetic pyrites. Chem. comp. : Fe 7 S 8 . Sulphur 39*5 ; iron 

 60-5 = 100. 



Hexagonal system. 



More of a copper-colour than the other pyrites, slightly magnetic, 

 and crystallizes in six-sided forms. 



It occurs with gold and calcite at Hawkins Hill. 



Nickel. 



Kupfernickel. — Copper-nickel. 



Chem. Comp. : Nickel arsenide = NiAs., Ni = 44*1 : As = 55-9 = 

 100. 



Hexagonal system : Massive. Of a copper-red colour, in parts 

 incrusted with pale green nickel hydrate. Reported from near 

 Bathurst. 



Plakodine. 



Arsenical nickel : NiAs., Nickel = 60 per cent. 



Found by the Rev. W. B. Clarke, on the Peel River, and to the 

 south-west of Weare's Creek. Yellowish white in colour, highly 

 magnetic. Sp. gr. — 8 \ H. = 5*5 ; and dissolving readily in nitric 

 acid. 



