238 



METALS. 



Composition of the pure ore : iron 70, and oxygen 30. 

 The varieties without a perfect metallic luster often contain 

 more or less clay or sand. Before the blowpipe alone infu- 

 sible ; with borax in the inner flame gives a green glass, 

 and a yellow glass in the outer flame. 



Dif. This ore is distinguished from magnetic iron ore 

 by its red powder ; and from any silver or copper ores by 

 its hardness and infusibility. The word hematite, from the 

 Greek haima, blood, alludes to the color of the powder. 



Obs. This ore occurs in both crystalline and stratified 

 rocks, and is of all ages. The more extensive beds of pure 

 ore abound in the primary rocks; while the argillaceous 

 varieties occur in* stratified rocks, being often abundant in 

 coal regions and other strata. Crystallized specimens occur 

 also in some lavas. 



Splendid crystallizations of this ore come from Elba, whose 

 beds were known to the Romans ; also from St. Gothard ; 

 Arendal, Norway ; Langbanshyttan, Sweden ; Lorraine and 

 Dauphiny. Etna and Vesuvius afford handsome specimens. 



In the United States, this is an abundant ore. The two 

 iron mountains of Missouri, situated 90 miles south of St. 

 Louis, consist mainly of this ore, piled "in masses of all 

 sizes from a pigeon s egg to a middle size church." One of 

 them is 300 feet high, and the other, the " Pilot knob," is 700 

 feet. Both the massive and micaceous varieties occur there 

 together with red ochreous ore. Large beds of specular 

 iron have been explored in St. Lawrence and Jefferson 

 counties, N. Y. ; Plymouth, Bartlett and elsewhere in New 

 Hampshire ; Woodstock and Aroostock, Maine, and Liberty, 

 Maryland, are other localities ; also the Blue Ridge, in the 

 western part of Orange county, Va. The micaceous variety 

 occurs at Hawley, Mass., Piermont, N. H., and in Stafford 

 county, Va. Lenticular argillaceous ore is abundant in 

 Oneida, Herkimer, Madison, and Wayne counties, N. Y., con- 

 stituting one or two beds 12 to 20 inches thick in a compact 

 sandstone ; it contains 50 per cent, of oxyd of iron, with 

 about 25 of carbonate of lime, and more or less magnesia and 

 clay. The coal region of Pennsylvania affords abundantly 

 the clay iron ores, but they are mostly the argillaceous carbo 

 nate of iron or limonite. 



What is the composition of specular iron 1 What are its distinguish- 

 ing characters ? What is its mode of occurrence 1 What is said ot 

 the iron mountains of Missouri 1 



