i3TS Examination of Ores of Iron. 



Examination of Iron Ores from the Northern Part of tht 

 State of New-York. By Issachar Cozzens. 



Read December 19th, 1825. 



The following examinations of some ores of iron, were 

 undertaken with a view of ascertaining the exact quantities 

 of iron, the presence of any other metallic oxide, and more 

 especially the nature of the gangue in which these ores occur, 

 whether siliceous, magnesian calcareous, or argillaceous. 

 It was desirable to introduce some improvement in the work- 

 ing of these ores, for experience had taught the proprietors, 

 that those which contained the greatest per centage of iron, 

 were not the most profitable to be worked, but on the con- 

 trary, as will be seen by the following analysis, many ores 

 which were mixed with a large proportion of earthy matter, 

 were more easily fluxed, and of course were more profitable 

 to the manufacturer. 



It appeared, therefore, that in this case the earthy matter, 

 which was granite, acted as a flux, and consequently that 

 granite or sienite, if containing much felspar, may be ad- 

 vantageously used as a flux for very rich ores of iron, where 

 these rocks are not naturally associated with the ores. 



The detection of a new mineral, or of new combinations 

 of minerals, does not seem to me to constitute the chief 

 value of an analysis. A more important end is attained, if 

 we can by analysis, throw out any hints which may improve 

 the manufacture of an article so essential to the wants of 

 mankind. 



No. 1. Ore of iron from Peru, Clinton County, New- 

 York. 



Character. Its powder is nearly black ; magnetic ; its 

 specific gravity 4,41 in the specimen examined; it gives 

 fire with steel. 



Analysis. One hundred grains coarsely powdered, were 

 submitted to pure muriatic acid, which dissolved ninetv 



