56 NEW YORK STATE MUSEUM 



Greenockite is found crystallized in Renfrewshire, Scotland, 

 and, associated with sphalerite, at the Bohemian locality and in 

 Pennsylvania and Missouri. 



It is mined for cadmium with the sphalerite. 



Millerite (capillary pyrites) NiS 



Millerite, the sulfid of nickel, contains 35.3$ sulfur and 64.7$ 

 nickel. 



It crystallizes in the hexagonal system but the crystals are 

 rarely of sufficient size to make this apparent, the lengthening 

 of the crystals producing hairlike forms which often radiate 

 from a center or form a mat or wad of interwoven individuals. 

 The capillary crystals are sometimes grouped in crusts of col- 

 umnar or radiated aggregates as in the specimen shown in 

 pi. 15 2 . The luster is metallic, the color a brass-yellow to 

 bronze-yellow and the streak greenish black. 



Millerite occurs in cavities as at the Antwerp locality, where 

 it is found in hematite, or incrusting as at the Pennsylvania 

 deposit where it overlies pyrrhotite. It is found in Bohemia, 

 Saxony and Cornwall and in the United States in Lancaster 

 county, Pa. and at Antwerp, Jefferson co. N. Y. 



It is a source of nickel. 



Niccolite (copper nickel) NiAs 



Niccolite is the arsenid of nickel and contains 56.1$ arsenic 

 and 43.9$ nickel; of which the arsenic is sometimes replaced in 

 part by antimony or sulfur, and the nickel by a little iron or 

 cobalt. 



Hexagonal crystals of niccolite are rare, the mineral usually 

 occurring in pale copper-red metallic masses of smooth, impal- 

 pable structure, with an uneven fracture. 



In addition to the European and South American localities, 

 niccolite occurs in the United States at Lovelock Nev., Till 

 Cove, Newfoundland, Silver Cliff Col., Chatham Ct. and to a very 

 limited extent at Franklin N. J. 



It is mined for nickel. 



Pyrrhotite (magnetic pyrites) 

 Pyrrhotite is a sulfid of iron of varying percentages of sulfur 

 and iron and often containing nickel. 



