230 METALS. 



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inner flame, a bottle-green glass. By their difficult fusi- 

 bility, the species with a metallic luster are distinguished 

 from ores of silver and copper, and also more decidedly from 

 these and other ores by blowpipe reaction and reduction. 



NATIVE IRON. 



Monometric. In regular octahedrons ; cleavage parallel 



to the faces of the octahedron. | Usually massive, with a 



more or less fine granular structure,./ 



& Color and streak iron-gray. Fracture hackly. Malleable 



land ductile. H=4'5. Gr=7*3 — 7*8. Acts strongly on 



Uhe magnet. 



Obs. Native iron, as it occurs in meteorites, is usually 

 ^alloyed with nickel and other metals. Whether terrestrial 

 native iron has been observed, is a question of some doubt. 

 a mass from Canaan, Conn., reported as of this character, 

 has been shown by Dr. A. A. Hayes to be artificial, beyond 

 doubt. Steinbach and Eibenstock in Saxony, and the mine 

 of Hackenberg have been mentioned as foreign localities. 

 Another occurs in Western Africa. 

 ■ Meteoric iron occurs in nearly all meteorites, and almost 

 I wholly constitutes a large part of those that have been dis- 

 covered. A mass weighing 1635 pounds is now in the 

 cabinet of Yale College ; it came from Texas. It contains 

 90 to 92 per cent, of iron T and 8 to 10 per cent, of nickel, 

 the alloy not being uniform throughout / Meteoric iron often 

 has a very broad crystalline structureTiong lines and trian- 

 gular figures being developed by putting nitric acid on a 

 polished surface.? The coarseness of this structure differs 

 in different meteorites, and serves to distinguish specimens 

 not identical in origin. The Texas iron is remarkable for 

 the large size of the crystallization. 



The most remarkable masses of meteoric iron occur in 

 the district of Chaco-Gualamba in South America, where 

 there is one whose weight is estimated at 30,000 pounds. 

 The large Pallas meteorite weighed originally 1600 pounds ; 

 it contains imbedded crystals of chrysolite. 

 / Besides nickel, which sometimes amounts nearly to 20 

 J per cent., meteoric iron often contains a smaj.1 per centage of 



What is the crystallization of iron ? its hardness, gravity, and other 

 character 1 How does it occur native ? What is said of meteoric iron I 



