I 



44 JV'otice of the localUy of Sulphate of^arytes, ^t^ 



of granite; on the surface, (C) the coal-mine- This has 

 been opened on either side of the brook, where it passes 

 through a narrovt ridge of green-stone. The coal has been 

 found only in the green-stone. Directly fronting this rock, 

 on the east, is a wall of sand-stone slate, at the base of which 

 * the brook runs. The coal was first found, and wrought, in 

 the bed of the brook, about twenty years ago; about six 

 years ago, a company in New-York made new openings 

 in either bank of the brook* The coal is found in veins in 

 connection with crystallized quartz; tbe quartz often appears 

 in geodes whose cavities are filled with coal; narrow veins 

 have their walls lined with crystallized plates of quartz, and 

 are filled with coal; the coal has never been found in large 

 masses : the largest that I have seen not more than two or 

 three pounds. The larger masses are foliated, shining, brit- 

 tle, and very bituminous; but it more usually has the ap- 

 pearance of cinders so mixed up with silicious matter as to 

 be hardly combustible. The sand-stone in its vicinity 1 have 

 not observed to be converted into shale. On the eastern 

 face of the green-stone ridge, forty rods north of (C), on the 

 west bank of the brook, is (D) the lead-mine. This was 

 first opened during the revolutionary war, and again about 

 fifteen years ago. Several of the old pits and heaps of rub- 

 bish remain ; the veins are found in a north by east direc- 

 tion; the minerals I have found in the rubbish are galena, 

 in small cubical crystals, foliated, and finely granular; the 

 crystals which are exposed to the air are often covered 

 with a thin pulverulent coat, or they are beautifully irides- 

 cent. Blende yellow and black, the latter rare ; it is in 

 much larger masses than the galena. Pyrites ; this is the 

 rarest of the three sulphurets; the gangue is sulphate of 

 barytes, resembling that of the former vein — often resem- 

 bhng coxcomb spar. Carbonate of lime; colourless and 

 crystallized, or foliated ; agatized, i- e. in layers of different 

 colours and textures, foliated, granular, and fibrous. The 

 fibrous layers are generally external, thin, with the fibres 

 perpendicular to the direction of the layers. Quartz in ge- 

 odes and crystallized plates, (a fine-grained green mineral, 

 resembling disintegrated green-stone.^*) On the eastern face 

 of the green-stone ridge, between (C) and (D,) the rock is 



* Chlorite? — this is fouud in similar cli'curaiitaiicps iu the green-stoue 

 x^car New-Haven. — Ed. 



