Geology of Cornwall

The rocks of Cornwall have an amazing story to tell. They have been on a journey of 8,000 miles in just 400 million years. This journey has included tropical seas, deserts, volcanic eruptions and hot granites, mineral vapours rich in tin and copper and ever-changing climate and sea levels. (Cornish Geology)

A true force of nature.

Cornish geology typically consists of black, folded slates and pale grey, blocky granites. But there are exceptions:

Polzeath Beach (north coast on the Camel estuary): Stripy slate formations in purple and pale greens.

polzeath (8)

Kynance Beach (south-west on the Lizard peninsula): Serpentinite cliffs are made up of dark green and red rocks, polished by thousands of years of crashing waves to look like shiny snakeskin.

kynance (7)

Up on the cliffs by Chapel Porth on the north coast the rocks were lighter and redder.

And at Boscastle (north coast, north Cornwall) I was intrigued by huge lumps of marble-like granite rocks along the pathway and on tops of Cornish stone walls.

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I have lived in the UK for most of my life, but when young I definitely had wanderlust and even ended up living in South Africa for several years which was a wonderful experience. I now look forward to a long and leisurely retirement doing what I like most - gardening, photography, walking and travelling.

49 thoughts on “Geology of Cornwall”

  1. I absolutely adore the colors. I just showed some of my students these pictures – they loved them as well!

  2. On our various hiking adventures, I developed a deep appreciation for rocks and rock formations. I regret not having some basic knowledge about geology because it is so interesting when you’re outside surrounded by magnificient rocks like the ones in your photos.

    I particularly love the purple and green rock. That’s a new one for me. I’ve never seen a purple rock. Absolutely gorgeous!

  3. Such variety in colours and textures Jude. Jack would be in seventh heaven here as he loves to collect rocks. We have boxes and boxes of them stashes away, as well as the hundreds on show around the garden.

      1. When we came here from NZ Jack actually left his stones with his son as we only brought a couple of suitcases with us to Australia, having sold everything, drastic minimalisation. But then a year later Jason came over here with everything he owned, including jacks stones, in a big container. Since then the stone collection has increased dramatically

        1. It is frowned upon to take stones from the beaches here. Shells are OK and sea-glass, but not rocks or pebbles. I must confess to having one or two myself though, even one from Australia and one from Namibia.

        2. I think you can take rocks and shells over here. Anyway Jack has collected buckets full all the way round Australia. Matilda was groaning with the weight of them by the time we got back home after a year on the road

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