It is wonderful part of geology to learn about coal and its properties, many people make their career in coal industry. So it is a necessary fact that we should know about basics of coal and geological location.

1. COAL
Origin
Distribution
Types

2. “Coal in truth stands not beside but entirely
above all other commodities. It is the
material energy of the country- the universal
aid, the factor in everything we do with coal,
almost any feat is possible; without it we are
thrown back into the laborious poverty of
early times” (DiCiccio, 1996).

3. COAL Coal is one of the principal mineral fuel
Defined by Stutzer and Noe as a
combustible rock which had its orgin in
the accumulation and partial
decomposition of vegetation.
Is a sedimentary rock usually found in
layers with other sedimentary rocks
such as shale, limestone and sandstone
Is not a metamorphic rock or igneous

4. COAL
Is a sedimentary rock usually found in
layers with other sedimentary rocks
such as shale, limestone and sandstone

5. Chemically coals are composed of
• Organic
• Mineral matter.
Organic mass consists of
• Carbon 60 to 90%
• Hydrogen 1 to 2%
• Oxygen 2 to 20%
• Nitrogen 1 to 3%
• And slight amount of sulphur and phosphrous.
• From lignite to anthracite there is a progressive
elimination of water, oxygen and hydrogen and an
increase in carbon.

6. Classification of Coal
• Vitrain
• Durain
• Clarain

7. Vitrain or (anthraxylon)
• constitutes thin bands of bright, glassy-
looking, jet like coal with conchoidal
fracture.
• The woody structure is not visible
megascopically. Its brilliance,
approaching jet, varies with the rank of
coal.
• Vitrain supplies cooking qualities

8. Durain
• Dull coal, lacking lustre and
having an earthy appearance.
• Hard, black to lead-grey in colour,
and consists of cuticles, spores.
• Formed in water less toxic than
for vitrain.

9. Clarian
• Forms as thin bands in coal
• Characterized by bright colour and silky
lusture.
• Composed largely of translucent attritus.
Attritus is finely divided plant residue composed of
the more resistant plant products.

10. Ranks and Kinds of Coal and Classification
Coals are divided into four main groups
Anthracite or hard coal
Bituminous or Soft coal
Lignite
Cannel Coal
Peat

11. Each groups is divided into ranks
The lowest rank upwards are
Lignite
Brown coal
Subbituminous
Bitiminous
Superbituminous (three ranks)
Semianthracite
Anthracite

12. Carbon
Peat
Lignite
Sub Bituminous
Bituminous
Anthracite
Coal Quality Pyramid –
lowest rank upwards are

13. PEAT
Peat is not coal eventhough it is a
fuel. It is an accumulation of partly
decomposed vegetable matter that
represent the first stage in the
formation of all coals.

14. LIGNITE
• Lignite (brown coal) is the second stage.
• Brownish black and is composed of
woody matter embedded in macerated
and decomposed vegetable matter.
• Banded and jointed and because of its
high moisture content, slacks or
disintegrates after drying in the air.

15. • It is subjected to spontaneous
combustion and has low heating value.
• It is used for local fuels and to make
producer gas, and in powdered form for
heating and steam rising.

16. BITUMINOUS
• Dense, dark, brittle banded coal that is
well jointed and breaks into cubical or
prismatic blocks and does not
disintegrate upon exposure to air.
• Vegetative matter is not ordinary visible
to the eye.
• Dull and bright bands and smooth hackly
layers are evident.

17. • Ignites readily and burns with a smoky
yellow flame
• Low moisture, medium volatile matter
and high fixed carbon and high heating
value.
• It is the most used and desired coal in
the world and serves for steam, heating
gas and cooking.

18. SUBBITUMINOUS
• Intermediate coal is often difficult to distinguish
from bituminous coal.
• Dull, black and waxy.
• Shows little woody matter, is banded, and splits
parallel to the bedding but lacks the columinar
cleavage of bituminous coal.
• Some varities disintegrate upon exposure.
• Good clean fuel but of relatively low heating

19. ANTHRACITE
Jet-black, hard coal that has high lustre, is
brittle, and breaks with a conchoidal
fracture.
Ignites slowly, is smolkeless, burns with a
short blue flame, has low sulfur comtent, and
has high heating value.
It is restricted in distribution and was used
exclusively for domestic heating and used for
producing carbon.

20. WHERE?
Worldwide - -

21. PEAT
Highly organic material forming a dark
brown mass—low energy value and high
moisture content

22. LIGNITE
Peat that has undergone anaerobic
(i.e. without oxygen) decay

23. SUB BITUMINOUS
Black coal formed under greater pressure
and overburden than lignite with higher
carbon content

24. BITUMINOUS
Highest quality soft(i.e bituminous) coal
containing high carbon and heat value

25. ANTHRACITE
Hard coal with highest carbon and energy
content. NE counties of PA.

26. Formation of coal
Organic matter derived mostly from land
plants accumulates in low-energy
environment (like a swamp).
Oxidative decay uses up lots of oxygen,
rendering the sediment pore waters
devoid of oxygen (anoxic).
Gentle cooking and pressing (lithification)
as a result of increasing burial depth
remove the pore water and increase
carbon content (due to release of volatile
components of the organic molecules).
Low grade coal (lignite) cooked very little.
High grade coal (anthracite) cooked a lot
(close to being a metamorphic rock).
Lower grade coal tends to contain
minerals such as pyrite, which formed
under the reducing (low-oxygen)
conditions.

27. Coal Characteristics
Lignite—25-35% carbon;
Sub bituminous—35-45% carbon;
Bituminous—45-86% carbon;
Anthracite—86-98% carbon;