32 ECONOMICAL MINEHALOGY. 



to be more extensive, at least it has been more extensively worked. This, like most of the 

 other ore beds in this district, is worked to the day, as it is technically called ; excavations 

 being made in various places from the surface of the ground, and the ore thus exposed, and 

 subsequently removed. 



In its mineralogical characters, this ore is quite similar to that found in the Fishkill bed ; 

 but perhaps there is a larger proportion of the ochrey or fine ore, as it is here called, which 

 is usually considered more valuable than the other varieties. Associated with this ore there 

 is occasionally found a bluish mass resembling specular oxide of iron, but which, upon exa- 

 mination, is ascertained to consist of minute crystals of oxide of manganese with a high me- 

 talUc lustre. This locality is further deserving the notice of the mineralogist, from the fact 

 that the rare mineral gibbsite is associated with the hematite. Previously to my announcing 

 its occurrence here in 1837, it had only been found at Richmond in Massachusetts. 



The following is the composition of a specimen of hematite from the Clove mine : 



Peroxide of iron, 80. 27 



Insoluble matters, 7. 43 



Water, 11.66 



Foss Ore Bed. Proceeding from the Clove bed in a northwestern direction, after crossing 

 Chesnut ridge, we come to a deposit of ore known by the above name. It is situated in the 

 town of Dover, about a mile and 'a half west-southwest from the furnace of the Dover Iron 

 Company. This bed is found in a vaUey between two spurs of the -mountain which passes 

 through this part of the county ; and it is particularly interesting as showing the association 

 of the hematite with the mica slate, which occurs here in strata of some thickness, and con- 

 tains garnets of various sizes and forms. In extent, however, this bed appears to be inferior 

 to either of those already noticed. The ore also is in much larger masses, does not exhibit 

 those beautiful imitative forms, and is not only with more difficulty reduced to powder, but 

 contains a larger proportion of foreign' substances. 



Amenia Ore Bed. This is found near Ameniaville, in the northwestern part of the town of 

 Amenia. This is an enormous deposit of hematitic iron ore, from which supplies are con- 

 stantly obtained for several furnaces in the vicinity. The bed has been opened at various 

 places for the distance of an hundred yards, and the ore presents all the varieties observed at 

 the other localities, and at the celebrated Salisbury Mine in Connecticut. It often occurs in the 

 form of stalactites of various sizes, and possessing uncommon beauty. The same high polish, 

 or blackish sooty matter, is observed on the inner surface of the nodules ; and they not un- 

 frequently have a light brown colour, and a structure so distinctly fibrous as to give them a 

 considerable resemblance to wood. There is also intermixed with the nodules of the brown 

 ore, a fair proportion of the yellow pulverulent ochre which is usually so much esteemed by 

 iron smelters. 



A fragment of a beautifully radiated stalactite from this locahty had a specific gravity of 

 3.828 ; and upon calcination, lost 13. 5, per cent of its weight. It is probably a specimen of 

 one of the purest varieties of this ore. Its composition was ascertained to be as follows : 



