ABSTRACT
As I write, I have in front of me three pieces of rock from the coast of the northwest Highlands of Scotland. The first is a pebble of pink granite, collected on the beach on the southwest corner of Mull. I had anchored my little yacht Coral in the narrow bay at Rubh’ Ardalanish and gone ashore to explore, picking it out from the beach as I returned. It was startlingly pink when I lifted it out of the cold water; now dry it is more subdued but still remains strongly coloured, its coarse crystalline structure evident to the naked eye. Granite is an igneous rock, its crystals formed in intense heat and pressure under the Earth surface, cooling as it bubbles through in dome-shaped formations. My piece of granite erupted some 50 million years ago as part of the major earth movements that formed the Highlands. In geological terms, it is broadly contemporaneous with the columnar volcanic basalt, most celebrated on the small island of Staffa, but generally common across this area.
