iron. 175 



magnetic quality distinguish it from pyrite ; and its pale- 

 ness of color from chalcopyrite or copper pyrites. 



Obs. Crystallized specimens have been found at Kongs- 

 berg in Norway, and at Andreasberg in the Hartz. The 

 massive variety' is found in Cornwall, Saxony, Siberia, and 

 the Hartz ; also at Vesuvius and in meteoric stones. 



In the United States, it is met with at Trumbull and 

 Monroe, New Fairfield, and Litchfield, Conn. ; at Strafford 

 and Shrewsbury, Vt. ; at Corinth, New Hampshire; in 

 many parts of Massachusetts and New York ; at Lancaster, 

 Pa. , where it is worked for nickel. It is used for making 

 green vitriol and sulphuric acid, like pyrite. 



Troilite is a similar mineral of the formula Fe S, occur- 

 ring in meteorites. Schreibersite is a phosphide of iron and 

 nickel, occurring in meteorites. 



Arsenopyrite. — Mispickel. Arsenical Iron Pyrites. 



Trimetric. In rhombic prisms, with cleavage parallel to 

 the faces /; 7a/=111° 40' to 112°. 

 Crystals sometimes elongated horizon- 

 tally, producing a rhombic prism of 

 100° nearly, with / and / the end 

 planes. Occurs also massive. 



Color silver-white ; streak dark 

 gravish-black. Lustre shining. Brit- 

 tle/ H. =5-5-0. G.=6-3. 



Composition. Fe AsS = Arsenic 46 *0, 

 sulphur 19-G, iron 34*4=100. A co- 



baltic variety contains 4 to 9 per cent, of cobalt in place 

 of part of the iron ; Danaite of New Hampshire, consists 

 of Arsenic 41-4, sulphur 17-8, iron 32-9, cobalt 6*5. B.B. 

 affords arsenical fumes, and a globule of iron sulphide 

 which is attracted by the magnet. In the closed tube a 

 sublimate of arsenic sulphide. Gives fire with a steel and 

 emits a garlic odor. 



Diff. Eesembles arsenical cobalt, but is much harder, 

 it giving fire with steel ; it differs also in yielding a mag- 

 netic globule before the blowpipe, and in not affording the 

 reaction of cobalt with the fluxes. 



Obs. Arsenopyrite is found mostly in crystalline rocks, and 

 is commonly associated with ores of silver, lead, iron, or cop- 

 per. It is abundant at Freiberg, Munzig, and elsewhere in 

 Europe, and also in Cornwall, England. 



