At the end of Gurnard's Head some exposed Pillow Lava can be found.
The Headland is composed of Greenstone .
The Pillow Lava is volcanic basaltic rock which erupted and cooled under water (370mya).
Later (290mya) the volcanic basaltic rock near the granite intrusion was changed by heat /pressure
into a hard dark rock , known locally as Greenstone
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Location - Gunard's Head is West of St Ives , near Treen - In Gallery 16
Ref: 1220.21
Date: 19/04/2015
Location: SW 4319.3870