' 



,mm * 



SPECULAR IRON ORE. — HEMATITE. iA^O 



Rhombohedral. In complex modifications of a rhombohe. 





. 



dron of 85° 58 ' ; crystals occasionally thin tabular. Cleavage 

 usually indistinct. Often massive granular; sometimes 

 jamellar or micaceous. Also pulverulent and earthy. 



* Color dark steel-gray or iron-black, and often when crys- 

 tallized having a highly splendent luster; streak-powder 

 ^herry-red or reddish-brown. The metallic varieties pass 

 „)into an earthy ore of a red color, having none of the external 

 -characters of the crystals, but perfectly corresponding to them 

 Avhen they are pulverized, the powder they yield being of a 

 ,deep red color, and earthy or without luster. Gr=4.5— 

 -5'3. Hardness of crystals 5*5 — 6*5. Sometimes slightly 

 "attracted by the magnet. 

 Varieties and Composition. 



Specular iron. Specimens having a perfectly metallic 

 luster. 



Micaceous iron. Specular iron, with a foliated structure. 

 Red hematite. Submetallic, or unmetallic, and of a brown- 

 sh-red color. 



Red ocher. Soft and earthy, and often containing clay. 

 Red chalk. More firm and compact than red ocher, and 

 of a fine texture. 



Jaspery clay iron. A hard impure ore, containing clay, 

 -and having a brownish -red jaspery look and compactness. 

 * *»■, Clay iron stone. The same as the last, the color and ap. 

 ^earance less like jasper. 



This is one variety of what is called "clay iron stone." 

 Much of it belongs to the following species, and a large 

 '<~*part also is spathic iron, as is the case with that of the Eng- 

 lish coal measures. 



Lenticular argillaceous ore. A red ore, consisting of 

 ^ small flattened grains, something like an oolite. 



Oligiste iron, iron glance, and rhombohedral iron ore, are 



W* other names of the species specular iron. 



, 



, What is the crystallization of specular iron ] What .are its physical 

 'characters? Describe, the varieties. ^ I j'Yfev Haaaa i 



V 7T* 



