566 
GEOLOGY OF THE FIRST DISTRICT. 
The Round-pond mine was opened many years ago, about one-fourth of a mile northwest 
of Round pond, and a considerable quantity of ore taken out, which appears very pure, and 
a good forge ore. Another opening was made a few years ago within one hundred yards of 
the northeast part, of Round pond, and several tons of ore taken out. 
Gneissoid and granitic rocks are associated with the iron ore at all these localities, and 
liornblende is a common mineral in the gneiss. 
The Forest of Dean mine is about three miles southwest of Mr. Kronkite’s mines, and 
about six miles west-northwest from Fort Montgomery. It belongs to George Ferris of New- 
York, and has been worked for many years. The ore forms a bed or vein of great size 
parallel to the strata of gneiss, and these dip to the east-southeast about forty to sixty degrees. 
A peculiar kind of granite is associated, but it seems to form imbedded and capping masses 
to the mass of ore. Excavations have been made, and ore taken out over a breadth of about 
one hundred and fifty feet; and at the depth of fifty to seventy feet, it is said the ore is a 
solid mass of that breadth. This bed of ere seems to be ext^isive and inexhaustible. Forty 
thousand tons of ore at least have been taken from this mine, and it seems as if a commence¬ 
ment of working it only has been made, if the bed be as broad as the indications and work¬ 
ings render probable. The nature and position of the rocks at this mine are illustrated on 
Plate 5, fig. 9. The ore has been removed in some places to the depth of sixty or seventy 
feet. The water is pumped up, and the ore raised up by means of a water wheel carried by 
a small stream a few rods west of the mine. The mine became very wet a few years ago, 
and was abandoned. The price of ore is kept so low, that it must be favorably located and 
easily mined to make it profitable. It is probable that this bed may be opened in many places 
in the vicinity. The same bed, it is supposed, associated with the same rocks, was seen 
about two miles farther up the stream to the southwest. 
The Greenwood mine is two miles southeast of the Greenwood furnace in Monroe. It is 
in the granitic gneiss. These layers of ore, separated by a few feet of rock, are e.xposed. 
The middle one of these only is sufficiently uncovered to reveal its thickness; this one is 
nine feet. This mine is covered by what some miners call a rider * that is, rock lying nearly 
or quite flat, or hanging in a direction contrary to the dip of the ore and rock in which it lies. 
This rock roof covers this mine ; after its removal, the ore and its walls lie conformably, that 
is, dipping to the southeast. The ore is mostly compact and hard, containing considerable 
sulphur, and requires roasting. It is associated with quartz, hornblende and mica. Prepara¬ 
tions are making to use it extensively. 
At Greenwood furnace the rocks are gneiss, with many masses of hornblende, augite, 
coccolite, and mica imbedded. In the vicinity of the beds of iron ore about one-third of a 
mile east of the furnace, several excavations have been made for the ore, which is more or 
less mixed with pyrites, and with slight traces of copper ore. Beautiful coccolite, and large 
crystals of mica and augite, have been procured from some of these excavations, 
“ Long mine is about five miles southwest of Southfield furnace, and two and half miles 
west of the saw-works. This mine has been known since long before the Revolution, and is 
the only one in the county at which any thing like systematic mining has been attempted. 
