ORES OF THE PRIMARY ROCKS. 
559 
(E). ORES OF THE HIGHLANDS, AND OF THE MOUNTAINS OF SARATOGA 
AND WASHINGTON. 
Magnetic iron is the only ore of any great economical importance known, but there are 
some beds of limonite, some of pyrites and of arsenical iron. Lead, silver and tin ores are 
said to have been found, but I have seen no indications to justify the conclusion that they 
occur in any important quantities. The beds of pyrites have already been described as 
localities of sulphate of lime and alum, on pages 114 and 119 of this volume ; it is unnecessary 
to repeat them. Copper pyrites and carbonate of copper have been observed in small 
quantities. 
^ (a). Highlands east of the Hudson. 
Magnetic oxide of iron. < {b). Highlands west of the Hudson. 
(. (c). Mountains of Saratoga and Washington counties. 
(a). Magnetic oxide of iron east of the Hudson. 
This ore is confined to the Highlands, and abounds in Putnam county. Several mines are 
already wrought, and many more are capable of exploration. They form masses in gneiss 
and hornblendic gneiss rocks, which, by casual examination, would be called beds ; but after 
a careful investigation of the facts, I think they may be called veins. Their course is parallel 
to the line of bearing of the strata, and they lie parallel to the layers of rock : but by close 
examination, it is found that in several instances, after continuing with this parallelism for a 
certain distance, the ore crosses a stratum of rock, and then resumes its parallelism; then 
crosses obliquely another, and so on. In other places, where a great bed of the ore occurs 
at some depth, only a few small stripes of ore penetrate through the superincumbent mass to 
the surface, as if the rocks had been cracked asunder, and these small seams of ore had been 
forced up from the main mass below. The beds or veins of magnetic iron ore lie either 
vertical, or dipping to the east-southeast, at an angle corresponding nearly to the dip of the 
strata. One example only was observed where its dip was to the west-northwest, viz. at the 
Stewart mine. The ore is very variable in quality. In some it is nearly pure magnetic 
oxide of iron; in others, it is intermixed more or less with the materials of the contiguous 
rocks; in others, it is mingled with pyrites and with other minerals. Two main veins of 
this ore will be described under the names of the Phillips vein and the Simewog vein. Nu¬ 
merous localities are known where this ore occurs, and where it has been dug in small quan¬ 
tities. They will be mentioned under the head of local details. 
