MAKE YOUR OWN COAL

You can make your own coal - or at least see how the process starts. Be aware, however, that the process will take several weeks and it can be very smelly. You will need somewhere outside where you can leave this experiment while it works.

You will need:

aquarium
fine/medium grained sand
fern fronds, twigs, plant leaves
sieve or sifter
fine silt
small trowel or similar

Aim:

To simulate and observe the conditions present during coal formation.

Method:

1. Place the aquarium outside in a safe place.
2. Spread about 5 cm of fine/medium grained sand all over the bottom of the aquarium.
3. Put about 15-20cm of water in the aquarium. (You can stop the sand moving around too much by placing a folded newspaper over it while you gently pour in the water.)
4. Drop in your collection of fern fronds, small twigs, and plant leaves. You need to get a good thick coverage of up to 10 cm.

Leave the layers for two weeks. Don't allow the plant material to dry out too much. In summer you may have to top up the aquarium with water to keep the plant layer below water level.

5. After two weeks observe the changes in composition and colour. What is happening? Record your results.

Leave the layers for another two weeks.…

7. Sift fine silt or sand on to the top of the decomposed plant material to a depth of about 10cm.
8. Wait a couple of days until the layers are well compressed, then remove any excess surface water and let the layers dry.

Leave the layers for two weeks.

9. Record your results.

10. When the layers are dry use the trowel or a small shovel to remove vertical sections of the material.
11. Carefully break the layers apart and observe the plant material.
12. Record your results.

Results:
It has taken you about 7 weeks to start a process which usually occurs over millions of years.
1. What has happened to the plant material? How has it changed in colour, composition, texture?

Further Investigation:
1. You will have noticed that the process got smelly. Why? What was happening here?
2. What do you think has happened to the energy which was contained in the plant material?
3. What did the fine silt/sand layer do to the plant material?

Further Activity:
1. Draw up two columns on a page. On the left hand side list the processes which you have observed in this activity. On the right hand side list the comparable processes which have taken millions of years. Have a look at the activity HOW COAL IS FORMED to help you.……

[coal]
[ironsands]
[JAGO]
[industrial minerals]
[aggregates]
[GNS]
[volcanoes]
[base & precious metals]
[rehabilitation]

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