MINERALOGY. 33 



ings have been made with the hope of profit in view. Chalcopyrite is 

 found associated with other sulphiirets in metalhc veins, and also in httle 

 deposits on the walls of dykes, and in the surrounding rocks. It is usu- 

 ally massive, but at times it shows evidences of crystallization ; and at 

 Copperas hill, across the Connecticut in Strafford, very pretty crystals, 

 formed by the twinning of two tetrahedrons, are found. As localities for 

 copper pyrites that are noteworthy, may be mentioned Bath, Franconia 

 (in gneiss rock), Madison, Haverhill, Warren (on Davis's farm), Lyme (east 

 of the east village), Jackson, Shelburne, Unity, Westmoreland, Littleton 

 (with bornite in White Mountain mine), Connecticut lake, Croydon, Plain- 

 field, Orford, Gardner mountain, and Monroe. 



A number of specimens of chalcopyrite from New Hampshire were 

 analyzed by Dr. Jackson,* but, as most of the analyses are of impure 

 specimens, which were selected as ores, they possess no value for a 

 report on mineralogy. It is suf^cient to say that Dr. Jackson found, by 

 his analyses, a number of ores sufficiently rich to be profitably worked. 

 Analyses of ores of copper from New England are, however, not at all 

 conclusive as to the value of mines. The following is Dr. Jackson's 

 analysis of chalcopyrite taken from H. Lang's estate in Bath. The an- 

 alysis agrees very well with the formula, and indicates quite pure copper 

 pyrites : 



Copper, 32.5 



Iron, 23- 



Sulphur 31.2 



Silica, 3.2 



99.9 



When occurring as a microscopic impurity in the rock, chalcopyrite is 

 recognized by the lustre, which is given to the light reflected from its 

 surface. Its deeper yellow color distinguishes it from iron pyrites. It 

 is not often met with in rock study. 



19. Arsenopyrite [Fe As S]. 

 Arsenopyrite or mispickel is not an uncommon mineral in our state. 



Geology 0/ New Hampshire, 1844, p. 2:3. 

 VOL. IV. 5 



