326 Gold Veins of the United States' Mine, Va. 



Near the surface, the vein dips to the west at an angle of 54° with 

 the plain of the horizon ; but as it gains in depth, it curves, gradually 

 approaching a perpendicular, until at the hundred and twenty foot 

 level, (the lowest point at which it has been cut,) where it makes^an 

 angle of 20^ with a perpendicular. 



The vein conforms with the stratification of the slate, the smooths, 

 or faces of which, sometimes form, for many feet, regular and beau- 

 tiful walls to the vein, which walls are as smooth as though they had 

 been chiseled; and were it not for their inchnation, the sides of the 

 tunnel at such places might be likened to the black walls of a large 

 and narrow dungeon. 



The matrix of the vein is quartz, cellular and laminated ; the 

 joints or faces of the laminse being thinly coated with the capel (?) 

 (decomposed shale,) of the lode, and sprinkled with argentiferous 

 galena, blende, (the black jack of mmers,) and sulphuretofiron ; fre- 

 quently spangles of gold may be seen lodged in the slate, when the 

 quartz is just from the mine, or is freshly cleft. It is difficult to 

 preserve such specimens, for when exposed to the air, whether in 

 the pile, or in the cabinet, the shale already disintegrated and nearly 

 in the form of clay, becomes dry and loses its consistency, when 

 the gold, having nothing to support it, falls off. In juxtaposition to 

 the pyrites, irregular crystals of the ferruginous sulphuret of copper 

 are occasionally seen, which from their peculiar yellowish hue, are 

 often taken for gold. Some specimens on their faces of cleavage are 

 studded with perfect and beautiful crystals of the phosphate of lead ; 

 these surfaces are frequently variegated with tints of black, brown, 

 purple and yellow ; and the green acicular prisms grouped in circles, 

 lines and broken curves, present the appearance of crescents, flowers, 

 etc. raised on the quartz in fancifully embossed work of green moss. 

 The molybdiate and venidiate of lead are also found in this vein. 



The thicknes of the vein is variable ; at some places it is near 

 three feet, at others it thins out into a mere thread or seam, then 

 widens again. After being cut by a cross-course of pure white 

 quartz, it thinned out, and entirely disappeared for a few feet. 

 Here its course was marked by a black seam between the walls ; 

 after driving a few feet on this seam, the vein was found replacing it. 



At the time when the fissure which contains this vein, was form- 

 ed, causes existed, to prevent regularity in the angle of inclination, 

 as well as in the course of the vein. At one place in the eighty foot 

 level the vein deflects from its course, forms almost a semicircle, 



