The pebbles on the shore at Gun Landing Cove in Cape Breton are colourful and patterned. They are best seen wet at the water’s edge but they are also stacked up in an embankment that curves around the bay at the highest tide mark. Most of the coloured varieties have a volcanic origin and are made of tuff from ash that spewed from the volcanic explosions or rained down in pyroclastic flows. The paler, greyer pebbles that sometimes display banding or layering are from later rocks which accumulated from fine sediments, that accumulated in a lake that lay in the valley between the inactive volcanoes, and became deformed layers of cherty siltstone. The volcanic rocks are very old indeed geologically speaking and date from the Neo-Proterozoic about 570 million years ago.
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