Worked Stone – Veltha by Emily Young

I am overwhelmed by the beauty of the Emily Young sculptures that are periodically exhibited in London locations for all to appreciate. Not only is the working of the stone exquisite but the selection of the stone for the work itself is amazing. As an amateur geologist I am fascinated by the range of colours, patterns, and textures naturally occurring in rocks, and to see them used to such great advantage is a privilege. I discovered an exhibition of Emily Young’s sculpted heads in the Southwood Garden attached to St James’ Church near Piccadilly on my last visit to London. They will be on display until January 2018. These pictures show aspects of a sculpted head called Veltha which is created in brecciated onyx, and it is displayed by courtesy of Bowman Sculpture.

A Stone Wall in Rethymnon

Apologies for the quality of these pictures taken way back in 2009 with my first digital camera. I just came across the images as I was sorting my photo collection. I took them on a holiday to Rethymnon on the island of Crete in the Mediterranean. At the time, I thought the strange patterns in the stone walls of the old Venetian fortress were part of the rocks themselves. Locally the bedrock is described as crystalline limestone. Looking at the pattern and texture now, I am not so certain. It looks more like something that has been caused by the weathering process. I am thinking that maybe over the centuries since the construction of the wall, the limestone has dissolved in rain water and the calcium has recrystallized in this way between the large and small rocks that make up the wall. This has in a way reinforced the wall by further binding the elements together. I don’t know whether the walls were originally built as dry stone or whether they incorporated mortar. The crystal formation seems to be acting as a mortar now.

I have seen something similar to this phenomenon on my beloved Rhossili Beach on the Gower Peninsula in South Wales. I will fish out some photos for comparison.

Portland Stone Sculpture at Tout Quarry

Dinosaur carving in Portland stone: Portland Stone sculpture at Tout Quarry, Isle of Portland, Dorset, UK, on the Jurassic Coast - dinosaur head (1)

 A selection of the Portland Stone sculptures at Tout Quarry on the Isle of Portland in Dorset, UK – animal-themed ones in this post.  Portland limestone has been quarried for centuries and used for the construction of many famous buildings such as St Paul’s Cathedral in London. The Isle of Portland has many quarries but some of these are no longer used for wholesale removal of stone. Tout Quarry near the Portland Heights Hotel is one of these disused quarries that is now a nature reserve and sculpture park. It is the most amazing place!

Click here to learn more about the incredible work being carried out by The Portland Sculpture and Quarry Trust.

Click HERE to find out exactly where to find the sculpture park and directions how to get there.

Portland stone seal: Portland Stone sculpture at Tout Quarry, Isle of Portland, Dorset, UK, on the Jurassic Coast - seal (2)

Portland Stone elephant head: Portland Stone sculpture at Tout Quarry, Isle of Portland, Dorset, UK, on the Jurassic Coast - elephant head (3)

Bear in Portland Stone:Portland Stone sculpture at Tout Quarry, Isle of Portland, Dorset, UK, on the Jurassic Coast - bear emerging from cave (4)

Portland stone dog head sculpture: Portland Stone sculpture at Tout Quarry, Isle of Portland, Dorset, UK, on the Jurassic Coast - giant dog's head (5)

Portland Stone bull: Portland Stone sculpture at Tout Quarry, Isle of Portland, Dorset, UK, on the Jurassic Coast - bull's head (6)

Portland Stone sculpture at Tout Quarry, Isle of Portland, Dorset, UK, on the Jurassic Coast - carvings of creatures among the rocks (7)

Portland Stone dinosaur carving: Portland Stone sculpture at Tout Quarry, Isle of Portland, Dorset, UK, on the Jurassic Coast - dinosaur (8)

Monkey face sculpture at Tout Quarry: Portland Stone sculpture at Tout Quarry, Isle of Portland, Dorset, UK, on the Jurassic Coast - monkey face (9)

Fish carved in Portland Stone; Portland Stone sculpture at Tout Quarry, Isle of Portland, Dorset, UK, on the Jurassic Coast - fish relief (10)

COPYRIGHT JESSICA WINDER 2011

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Stone steps on The Cobb

Stone steps on The Cobb at Lyme Regis, Dorset, UK, on the Jurassic Coast (1) 

Following on from comments received on yesterday’s blog posting about Portland Roach rock used in the building of The Cobb at Lyme Regis, Dorset, on the Jurassic Coast, here are some pictures of the precarious stone steps on the harbour wall. Does the photograph above show where Louisa Musgrave fell? Or maybe one of the flights of steps shown below? They are certainly very slippery in wet weather and difficult to negotiate when it is windy.

Stone steps on The Cobb at Lyme Regis, Dorset, UK, on the Jurassic Coast (2) 

Stone steps on The Cobb at Lyme Regis, Dorset, UK, on the Jurassic Coast (3)

Revision of a post first published 11 May 2010

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Blue Lias strata at Lyme Regis Part 1

Blue Lias rocks: Blue Lias rock strata on the seashore at Monmouth Beach, Lyme Regis, Dorset, UK, on the Jurassic Coast World Heritage Site (1)

The greater part of the cliffs on Monmouth Beach at Lyme Regis in Dorset, UK, on the Jurassic Coast, are made up of the Blue Lias sediments laid down in the Lower Jurassic Period. They are composed of alternating layers of hard pale limestone and softer, finely-bedded, shales and mudstones. The rocks of the cliff face are rapidly eroding back. Wave action and weathering wear away the softer layers so that the harder rocks above them are no longer supported and this leads to frequent falls of the stone down to the shore below.

The rock strata stretch out horizontally from the base of the cliff and extend seawards as a hard limestone rock pavement. This platform is also subject to wave action that breaks it up – resulting in a series of wide steps across the seashore in some places. These steps reveal the layering of the different strata, echoing that seen in the cliffs. Thinly layered, dark, soft rocks are sandwiched between lighter-coloured more resistant ones. Whilst the horizontal surfaces of hard limestone form the ‘treads’ of the steps, the softer, darker, shaley rocks form the ‘risers’. 

The photographs in this post illustrate the junction between the two rock types on the beach – the edges of the ‘steps’. Viewed from above, with midday sun casting strong shadows, the contrasts in colour and texture are emphasised. The natural pattern made by the cracking and delamination of the layers of rock assumes an abstract graphic quality.

Natural rock patterns: Blue Lias rock strata on the seashore at Monmouth Beach, Lyme Regis, Dorset, UK, on the Jurassic Coast World Heritage Site (2)

Jurassic rock pattern: Blue Lias rock strata on the seashore at Monmouth Beach, Lyme Regis, Dorset, UK, on the Jurassic Coast World Heritage Site (3)

COPYRIGHT JESSICA WINDER 2011

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One Charmouth pebble – seven aspects

A pebble with remarkable natural markings from Charmouth, Dorset, UK - part of Jurassic Coast (View 1) 

The markings on this pebble are entirely natural and exactly as found on the beach. Since I first found it, the white lines have remained unchanged but the dark colour of some patches has diminished with time. I have concluded that the dark patches were due to a damp surface film of microscopic algae or other micro-organism colonising those areas of the limestone with a coarser texture. These have eventually dried out and become inconspicuous.

White lines are wrapped around the pebble as if inscribed by an unknown artist, delineating curving abstract or geometrical spaces. Each angle of view reveals new aspects of the design. Pebbles with white lines and white patches on them are commonly found on the beach at Charmouth but this particular stone is astonishing in the intricacy of the markings. It is difficult to believe that the lines are natural but they are just the way I discovered them; they are a geological phenomenon and part of the petrology of the rock from which the pebble is derived.

A pebble with remarkable natural markings from Charmouth, Dorset, UK - part of the Jurassic Coast (View 2)

A pebble with remarkable natural markings from Charmouth, Dorset, UK - part of the Jurassic Coast (View 3)

A pebble with remarkable natural markings from Charmouth, Dorset, UK - part of the Jurassic Coast (View 4)

A pebble with remarkable natural markings from Charmouth, Dorset, UK - part of the Jurassic Coast (View 5)

A pebble with remarkable natural markings from Charmouth, Dorset, UK - part of the Jurassic Coast (View 6)

A pebble with remarkable natural markings from Charmouth, Dorset, UK - part of the Jurassic Coast (View 7)  

Revision of a post first published November 2009

COPYRIGHT JESSICA WINDER 2011

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Oregon Coast Rocks Part 2

Oregon rocks: Rock pattern and texture caused by spheroidal weathering in cliffs at Smelt Sands State Park on the Oregon Coast in the U.S.A. as seen from Trail 804 (7)

Here is something geological that I have never noticed in my usual haunts in the UK. These strange patterns and textures were observed in cliff rocks at Smelt Sands State Park on the Oregon Coast in the U.S.A. They were visible from the famous Trail 804. At first I thought they represented some sort of turbulant conditions in the distant past that had disturbed the deposition of rock layers. However, a bit of research seems to indicate that they are examples of spheroidal weathering of the rocks. This would appear to be the physical and mechanical result of chemical decomposition processes in the rock.

The geological forms shown in these photographs seem to match the illustrations of spheroidal weathering in a textbook I picked up while over in Oregon. According to Harold L. Levin, author of Contemporary Physical Geology published by Saunders College Publishing, 1990, ISBN 0-03-031139-x

spheroidal weathering is a term used to describe the spalling away of concentric surficial shells of the rounded surface of a boulder or rock mass. Such onion skin weathering is believed to result primarily from the mechanical effects of chemical weathering. When feldspars decompose, the clay product has greater volume than the parent feldspar. The increase in volume disrupts the interlocking texture of mineral grains in the rock and causes breakage and separation of the layer of partially weathered rock near the surface.

On smaller rocks and boulders this process is known as spheroidal weathering while the loss of concentric plates from larger rock surfaces is termed exfoliation.

Again, I am hampered by my lack of geological knowledge. So if anyone reading this can correct any errors I may have made, I would be pleased to hear from them.

The baseline for me is that I like the way the rocks looked – the colours, patterns and textures that to my eye constitute wonderful natural abstract images.

View of the beach at Smelt Sands State Park on the Oregon Coast, U.S.A. from Trail 804, where the spheroidal weathering is visible in the iron-stained cliff rocks (8)

Rocks of the Oregon Coast: Rock pattern and texture caused by spheroidal weathering in cliffs at Smelt Sands State Park on the Oregon Coast in the U.S.A. as seen from Trail 804 (9)

Rocks of the Oregon Coast: Rock pattern and texture caused by spheroidal weathering in cliffs at Smelt Sands State Park on the Oregon Coast in the U.S.A. as seen from Trail 804 (10)

Rocks on the Oregon Coast: Rock pattern and texture caused by spheroidal weathering in cliffs at Smelt Sands State Park on the Oregon Coast in the U.S.A. as seen from Trail 804 (11)

Rock colour, pattern and texture in spheroidal weathering: Rock pattern and texture caused by spheroidal weathering in cliffs at Smelt Sands State Park on the Oregon Coast in the U.S.A. as seen from Trail 804 and showing colours of decomposing iron minerals (12)

COPYRIGHT JESSICA WINDER 2011

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