Metamorphism - that's Greek for 'change of shape' isn't it? This is our latest Earth-related activity.The concept of metamorphism is a difficult one to explain because the processes happen at considerable depth in the crust or mantle and cannot be readily reproduced in a school laboratory. The activities given here demonstrate the principle of the effects of pressure on particles of different shape and composition, but cannot reproduce the recrystallisation that accompanies real metamorphism. However, slate and marble are important constructional and decorative materials and it is useful for pupils to have some understanding of their origins.
(The photo shows a Welsh craftsman splitting roofing slate)
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