Golspie beach, along with many other local beaches, is littered with lumps of exotic rock - in the sense that they didn't originate here. This is an example, a metamorphic rock called a gneiss. To my knowledge, the nearest outcrops of this sort of rock are to the west of us or in Norway, so the only way they can have been brought in is by the ice that covered the area some 10,000 years or more ago.
As the glaciers retreated at the end of the last ice they left great piles of boulder-clay, that is, material that contained an unsorted mixture of everything from boulders to clay. The rivers that worked the land along the ice front then sorted this sediment, as rivers do, bringing many of the boulders down to the coast where the sea has been moving them around ever since. One of the characteristics of ice worn rocks is that they are angular, often having been ripped off the basement rock under the glacier as it passed. That these rocks are now relatively rounded is down to the action of waves and running water.
This is but the recent history of this rock, and a brief history at that. How the rock itself was formed is a much longer story, spanning many millions of years.
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