Carbon and Fossil Fuels

• Lignite is a low grade brown coal, which is soft with high moisture content.
• Bituminous coal is the most popular coal in commercial use. 
  
• Anthracite is the highest quality hard coal.
  
• Magnetite is the finest iron ore with a very high content of iron up to 70 per cent. 
  

• Type of coal that is used commercially is bituminous coal.  Bituminous coal or black coal is a relatively soft coal containing a tar like substance called bitumen.
  
• This coal is graded based on plasticity, moisture content, volatility and ash content.
  
• Plasticity is essential for the production coke which is useful in making fuel gases like producer gas etc.
  
• Volatility is essential for steel making and power generation.
  

The most superior quality coal is anthracite. It has highest carbon content with 92.1% to 98% carbon. It ignites with difficulty and burns with smoke. China accounts for major production worldwide. It has fewest impurities and highest calorific value after graphite.

Peat, lignite, and bituminous are all types of coal (sedimentary), while graphite is an allotrope of carbon formed through metamorphic processes.

Anthracite is the best quality of coal with least ash content. Anthracite is a hard, compact variety of mineral coal that has a high luster. It has the highest carbon count and contains the fewest impurities of all coals, and has the highest calorific content as compared to other types of coals such as bituminous coal and lignite.

Haematite is a reddish-black mineral and an important ore of iron. It has a high iron content of 70 percent. It can be found in areas of volcanic activity or hot springs. Much hematite occurs in a soft, fine-grained, earthy form called red ochre.

Bituminous coal or black coal and Lignite coal are relatively soft. Bituminous is a higher quality than lignite coal but of poorer quality than anthracite.

Anthracite is a best quality coal. Its carbon content is 90% to 95%. Its burns slowly and great heat, with very little smoke.

Lignite is a lower grade coal and contains about 40% to 60% carbon. It has low heating power and emits smoke. Its colour varies from dark to black brown. 

Peat is the first stage of transformation of wood into coal and contains 30% to 45% carbon, sufficient volatile matter and lot of moisture. Its heating capacity is low and normally used as domestic fuel. 

Peat is the first stage of transformation of wood into coal and contains less than 40% to 55% carbon, sufficient volatile matter and lot of moisture. Its heating capacity is low and generally used as domestic fuel.

The yellow colour flame is seen when bituminous coal is burnt due to incandescence of very fine soot particles that are produced in the flame. This type of flame only burns at around 1,000 °C. Depending on the lighting, you may have actually seen the soot rising from the flame.

Anthracite is the best quality coal. It burns slowly and generates great heat, with very little smoke. Its carbon content is 80 to 95%. Only 5% of the world's coal is of this type.

Bituminous coal contains moisture up to approximately 17 percent. About 0.5 to 2 percent of the weight of bituminous coal is nitrogen. Its fixed carbon content ranges up to approximately 85 percent, with ash content up to 12 percent by weight.

Anthracite is relatively rare compared to other forms of coal, accounting for approximately 5% of the world's total coal reserves.