ORES OF THE PRIMARY ROCKS. 
561 
This mine was the first known and first worked in this part of the country. The ore was 
carted to great distances, and shipped on the North river, to some of the towns on Long- 
island sound, and various parts of the country. The largest portion of the ore was carried to 
Danbury in Connecticut, and was there an article of traffic. It has not been wrought for 
twenty or thirty years, in consequence of other beds having been found in more convenient 
locations for smelting and transport. Fifty thousand tons of ore, at least, have ^been taken 
from this mine, estimating four tons to the cubic yard; and one hundred thousand tons more 
may probably be taken from the vein in Simewog hill, without going below the level of the 
small stream which flows across the ore bed. Should it ever be necessary to obtain this ore 
in quantity, (as is probable, from the prospect of the New-York and Albany railroad passing 
up the valley on the east side of the hill,) at least one million tons may be calculated on, 
above the water level of the Croton river, which flows along the base of the hill, and free 
from the expense of drainage, by driving an adit level from the level of the Croton, a distance 
of three hundred or four hundred yards to intersect the vein. 
This vein of ore has also been worked to the extent of several thousand tons, near the road 
and north of the little stream mentioned above as crossing the vein. The vein here is from 
eight to fourteen feet thick, and nearly vertical in position, between strata of gneiss and horn- 
blendic gneiss which dip seventy to eighty-five degrees to the east-southeast. On Simewog 
hill, one-fourth of a mile south, the vein is from three to twenty feet thick, associated with 
similar rocks and with granite. It has been wrought on Simewog hill from thirty to sixty 
feet or more in depth, over a length of three hundred to four hundred yards. It is scarcely 
doubted, from the observations made, that this vein is at least two miles in length, with an ave¬ 
rage width of six feet. Its depth cannot be estimated, but it is presumed that the labor of 
ages could not exhaust it in depth, as the bottoms of such veins have never, in any country, 
been found. In the estimates above, the calculation is based upon the vein being wrought 
down to the water level of the adjacent valley. 
This ore bed seems to be a vein, although its strike is the same as that of the strata. In 
the excavations on Simewog or Mine hill, the bed or vein seems to have crossed the strata 
very irregularly and obliquely, as represented on Plate 5, fig. 12, and similar to the lead vein 
in the Shawangunk mountain at the Sullivan mine, running between the strata for a certain 
distance, then crossing obliquely between two other strata, and so on. 
The Phillips vein has been traced at short intervals for about eight miles, and is presumed 
to be continuous through this distance, except where it is interrupted by dykes and transverse 
heaves of the strata. Many mines have been opened on this vein, and several of them are 
now worked. 
The Coldspring and Patterson turnpike crosses this vein of iron ore near the crest of the 
mountain, about nine miles from Coldspring landing. There is an opening near the road, 
and near this crossing, where some ore has been dug. Here the ore seems injected in little 
sheets, veins and beds, through the gneiss rock, so as to form one-fourth to three-fourths of 
its mass through a horizontal thickness (as the strata are vertical) of thirty to thirty-five feet. 
Pyrites abound in a portion of the bed. The ore is easily traced along its course, as it shows 
Geol. 1st Dist. 71 
