MAGNETIC OXIDE OF IRON. 13 



A specimen of the magnetic sand from the banks of the Moose, gave, upon analysis, the 

 following results, viz : 



Silica and titanic acid, ,. ,. 5.16 



Magnetic oxide of iron, 94 . 84 



Washington County. An extensive bed of magnetic iron ore occurs in the town of Fort- 

 Ann, four miles north of the village of the same name ; the ore, however, is largely mixed 

 with black garnet, granular and crystalline hornblende. There are also similar deposits near 

 Mount-Hope furnace in Fort-Ann. The ore is magnetic, and sometimes exhibits polarity. It 

 lies in beds, sometimes pure, and sometimes intermixed with garnet, coccolite or hornblende. 

 Some other localities are noticed by Mr. Mather.* 



The following is the composition of a specimen of magnetic iron ore froull Fort-Ann : 



Protoxide of iron, 42. 26 



Peroxide of iron, 53. 69 



Insoluble matters, 4. 05 



Warren County. The magnetic oxide of iron is found on French mountain, three miles 

 south of the village of Caldwell, and some expense has been incuiTed in the excavations 

 which have been made. The ore is strongly magnetic, and possesses polarity. It is usually 

 massive, but octahedral crystals are also occasionally obtained. The associates are white and 

 red feldspar, of which large and handsome cleavages are abundant. These sometimes contain 

 grains of quartz. As a locality of iron ore, this is of very little consequence. Aside from 

 the great difficulty of access, there is as yet no evidence that the ore exists here in any 

 quantity. 



At Warrensburgh, near the East river, twelve miles from the village of Caldwell, this 

 mineral has been found in beds of considerable extent, and has there been worked by the 

 bloomery process. In one of these beds the ore was at first of good quality, but it gradually 

 changed its character when the mining was continued, until at length it became unfit for use. 

 This ore has a granular structure, the grains being of various sizes and colours, and evi- 

 dently consisting of different minerals. It is easily reduced to powder, and the gi-ains are 

 sometimes held together by so feeble a cohesion, that they may be separated by a slight blow 

 of a hammer. The whitish or transparent particles are usually about the size of a pin's head, 

 are scratched by fluor spar, and effervesce with acids. Small scales, of a steel grey colour, 

 which soil the fingers and give a blackish trace upon paper, are also disseminated through the 

 mass. 



From this description it is evident that the results of the analyses of this ore must be more 

 or less discordant. The following is the mean of several trials : 



Magnetic oxide of iron, 70. 80 



Carbonate of lime, 25. 00 



Plumbago, 3.00 



Silica, and loss, 1.20 



' Ntw- York Geological Reports, 1841. 



