28 PHYSIOGRAPHY. 



Anthracite. 



with Tourmaline and lolite at Haddam, (Con.) It also occurs with 

 Quartz in mica-slate, at Chesterfield and Bhndford, (Mass.) 



ANTHRACITE. Non-Bituminous Mineral- 

 Coal. MOHS. 



No regular form or structure. Massive, generally im- 

 palpable ; rarely vesicular, and sometimes divided into co- 

 lumnar masses, meeting in rough faces. 



Fracture conchoidal, often perfect. 



Lustre imperfect metallic. Color iron-black, sometimes 

 inclining to greyish black, often beautifully tarnished. 

 Streak unchanged. Opake. 



Not very brittle. Hardness = 2-0 ... 2*5. Sp. gr. = 

 1-4. 



1. The Columnar Glance- Coal of JAMESON, and the Mineral Car- 

 bon, or Mineral Charcoal, are both varieties of Anthracite. The for- 

 mer is remarkable for its irregular columnar composition, which is prob- 

 ably produced by fissures, and the low degree of lustre in its fracture : 

 the latter occurs in thin layers and massive specimens of a very delicate 

 columnar composition, and presenting a silky lustre. 



2. The varieties of the present species do not contain any bitumen, but 

 consist wholly of carbon, occasionally mixed with a small proportion of 

 oxide of iron, silica and alumina. They are inflamed with difficulty, and 

 burn without smoke or bituminous smell and with little or no flame, 

 leaving a more or less considerable earthy residue. 



3. Anthracite is found occasionally in more ancient rocks ; but its prin- 

 cipal deposits are in secondary strata, consisting of coarse sand stones, 

 greywacke and slate. It is sometimes met with in veins traversing trap 

 rocks. 



4. Vast deposits of Anthracite are found in the United States. The 

 most celebrated of these is the anthracite region, so called, of the Sus- 

 quehanna, situated chiefly in Luzerne county, (Pen.) It is between 

 sixty and seventy miles long, and about five broad, constituting a trough 

 or elongated basin, through which the Susquehanna river and Lacka- 

 wanna creek, flow. The Anthracite breaks out throughout this region 

 in precipices and hills, forming in some places the beds of the rivers and 



