84 
GEOLOGY OF THE FIRST DISTRICT. 
Acicular sulphate of lime was seen incrusting magnetic oxide of iron, at a mine where 
pyrites abound in that ore in the Phillips vein, eight and a half miles from Coldspring on the 
road to Putnam court-house in Putnam county. The specimens were very delicate and beau¬ 
tiful. 
Near^the junction of the water limestone with the underlying rocks, is a stratum abound¬ 
ing in pyrites. Sulphate of lime is formed in many places near this junction; and in one 
place, a trial of the pulverized rock was recommended as a substitute for gypsum,* as it is a 
limestone loaded with minute crystals of pyrites, which decompose and form a sulphate of 
lime. The material is stated to answer a good purpose, and to have produced an improve¬ 
ment in the luxuriance of vegetation (when scattered in stripes over the ground), that was 
visible at a great distance. This locality is at the High falls of the Rondout, in Ulster county. 
Numerous other localities were observed, where this pyritous stratum was near or interlami- 
nated with limestone, or where sulphate of lime was forming ; but so situated that it could 
not be used on account of the expense of transportation, or of its being too small in quantity. 
Sulphate of lime is deposited from the water of some of the sulphur springs at Sharon, 
Schoharie county. Some of it is said to be anhydrous. 
Sulphate of alumina, alum, and sulphate of alumina and iron, were seen efflorescing on 
rocks containing pyrites in many places. These salts generally accompany each other, and 
sulphate of iron is also found with them at most of the localities.f 
In Dutchess county, two localities were pointed out to me by Prof. Merrick, where there 
is an efflorescence of alum and sulphate of alumina. It occurs as an efflorescence, and in 
tuberculated masses and stalactites. One is on the mountain about two and a half miles 
southwest of Ameniaville, in decomposing' pyritous and dark colored mica slate, that was 
once supposed to contain coal; the other is about three miles south of the same village, in a 
similar rock. There is another locality in the township of Northeast. Prof. Merrick observed 
a locality of “ alum slate,” like that of Amenia, near the top of the hill east of Hurd’s 
corners in Pawling. 
In Putnam county, there is a locality of sulphate of alumina and iron, and of sulphate of 
iron, in Phillipstown, on Anthony’s Nose mountain, about three miles from West-Point, at 
an old iron mine where the ore contains pyrites. The earth from this place was used many 
years since by some of the inhabitants, for dyeing. Another locality is near Luddington’s 
corners, half a mile east, in Kent; another in the same township, four or five miles south, 
near Dean pond. 
In Orange county, near Fort Montgomery, in several places these salts are found efflo¬ 
rescing on rocks containing pyrites. 
* Vide Assembly Document No. 50, Geological Report for 1840, p, 245. 
t Alum has been described as efflorescing on the Catskill mountain (Cleayeland’s Mineralogy, p. 228, and Webster’s Catalogue, 
p. 12), as twelve miles west of Catskill; on the mountain four miles north of the Clove; and on the same mountain southwest of 
Cairo, in a stalactitical form. Also as existing in a spring on the north side of the mountain north of the Kaaterskill clove, one- 
quarter of a mile from Absalom Smith’s (Robinson’s Catalogue, p, 120; Silliman’s Journal, Vol. 4, p. 249). 
