The Carbonate Ore of the Hudson River. 63 



From north to south the several openings are here noted in the 

 order of their succession, beginning with 



PLASS HILL OPENINGS, in Greenport.— The ore has been 

 uncovered and tested for a distance of 1,000 feet, approximately, and 

 to a depth of 50 feet, in places, by a line of open cuts, which are from 

 10 to 100 feet below the top line of the ridge, and about 300 feet 

 above the river. The dip of the beds is 25°-30° N. 80° E., and the 

 thickness of the ore ranges between 10 and 16 feet, but in it there are 

 some thin layers of shale. The foot- wall rock is a drab-colored shale ; 

 the hanging-wall strata are gray sandstone. The ore is of a gray 

 shade where not weathered. It contains some quartz in small grains 

 and scattered nodules of pyrite. According to the reported analyses 

 it is rather lean, and is a non-Bessemer ore. These openings* are a 

 part of the Hudson River Ore and Iron Company's property. They 

 are less than a mile from the river, at Catskill station. 



South-east of Plass Hill and east of Plass Corner, the ore has been 

 uncovered in two small openings near the road to Greenport church. 

 It is lean and in thin and irregular seams. 



Southward there is a gap in the range where it is concealed under 

 the terrace formation of the Hudson River. It reappears at the 

 foot of Cedar Hill. 



CEDAR HILL OPENINGS. Cedar Hill and Mt. Thomas (or 

 Miller Hill), make up the ridge sometimes known as Long Hill. On 

 Cedar Hill the outcrop is on the crest, and is 400 to 450 feet above 

 tide level. There are several open cuts on the lands of the Hudson 

 River Ore and Iron Company, but none of them exceed 25 feet in 

 depth. The dip of the beds is on an average 40° N. 80° to 85° E. The 

 thickness of the ore varies from eight to 30 feet, including, in places, 

 some interbedded sandstone and also some slaty rock in the ore. No 

 work has been done since 1885, except in the new cut at the south 

 end of the hill, which was opened in 1888. 



LIVINGSTON'S MINE is east of the openings of the Hudson 

 River Ore and Iron Company, and near the top of the ridge. The 

 principal opening is a vertical shaft, 40 feet deep to the ore, then de- 

 scending in the ore, eastward. The dip is 35° east-north-cast. The 

 thickness of the ore is 18 feet. The large amount of silica, in much 

 of it, reduces the percentage of metallic iron, and it is non-Bessemer 

 also. The mining plant comprises a hoisting engine, pumps, an air- 



