Cassiterite-Tourmaline Vein - Goonbarrow (#23)
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Fact sheet
Description: 

Although the St Austell granite complex is famous for its china clay deposits it was at one time also the site of tin mines. This sample was collected from the Imperial lode in Goonbarrow china clay pit. Many thanks to Jeremy Hooper (Imerys Ltd) for providing the sample.

The colour of the tourmaline is why the old miners called this rock type "blue peach".

Note (in thin section) how the tourmaline and the cassiterite crystals are zoned - testimony to the rapidly changing conditions in a magmatic-hydrothermal environment. 

In Place
In Time
Location description: 
Goonbarrow china clay pit, near Bugle, Cornwall
Accuracy:
Timescale:
Timescale: 
Permian
Ma = Millions of years ago
In Focus
Collection:
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Type:
Type: 
igneous
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Rock-forming minerals:

Rock forming mineral:

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