A look ahead to the Flux: Salt and Glass exhibition at Lion Salt Works Museum

Blue glass pieces

Glass on display (and made) at The World of Glass - Credit: Andrew Pratt

A major new exhibition opens examines the region's contribution to the past, present and future of glass. Fiona Young talks to experts in the industry that has a fascinating past and a bright future

Glass is all around us but, of course, is mostly hidden in plain sight. From the windows of our homes to spectacles, light bulbs and microscopes to windscreens, cameras and computer screens, its transparency, flexibility and ubiquity is a hidden wonder.

This year is the United Nation’s International Year of Glass and Cheshire’s Lion Salt Works Museum is celebrating because salt has played a key but often forgotten role, in the history of glass.

The multi-award-winning museum’s In Flux: Salt and Glass, from July 11 to October 1, at its historic site in Northwich, celebrates the story of glass in the North West through the eyes of people who work in the industry. It shows how the production of the salt-derived flux, sodium carbonate, made using salt from Cheshire's vast salt deposits, gave a natural advantage to glassmakers in the region. 

Victorian stained glass

Victorian stained glass after conservation at Recclesia Stained Glass - Credit: Andrew Pratt

The colourful exhibition will explore how the region's growing expertise in glassmaking in the 19th century, led to revolutionary breakthroughs and explores glass through the eyes of people who work with glass in the region – from a curator of Roman glass at Chester's Grosvenor Museum, and Recclesia, a leading glass restoration company  – to Encirc, one of the country's biggest glass bottle manufacturers.

A leading North-West architect will consider the role of glass in building design and the exhibition concludes with an update on the new sustainable glass research and development company, Glass Futures, which will be based in St Helens. westcheshiremuseums.co.uk

Glass blowing

Molton glass being worked by skilled glassblower at World of Glass - Credit: World of Glass

Glass acts

Kate Harland, museum and heritage manager, West Cheshire Museums
Glass is a wonder material but, throughout history, one aspect of its production has caused headaches for glassmakers.  Furnaces must be heated to very high temperatures to melt glass. So a flux that could reduce the melting point, making glass easier and cheaper to make, was a valuable commodity. 
A common flux is soda ash (sodium carbonate), which is made from salt. It is such a successful flux that today it is used in most modern glassmaking.  The plentiful supply of salt from open-pan, salt-making sites, like the Lion Salt Works, was a key reason why soda ash factories grew up in this region. For instance, in 1873, Brunner Mond was established in Northwich, bringing pioneering processes to the large-scale production of soda ash. In turn, the easy availability of this flux gave a competitive advantage to the region’s 19th-century glass producers, laying the foundations for the world-renowned glass hub, St Helens in Lancashire.

Roman glass

Selection of second-century Roman glass from Chester's Grosvenor Museum - Credit: Andrew Pratt

Julie Edwards, archaeology officer, Grosvenor Museum, Chester
Though the world’s earliest glass dates from ancient Mesopotamia, it was the development of glass blowing in the mid-first century BC and the growth of the Roman Empire that took glass to a new level.
In Chester’s Grosvenor Museum, we have a fragment of a Roman window pane, made by pouring molten glass onto a tray and you can see the curving thumb-shaped edge formed by the side of the tray. In common with most of the first and second-century pieces pictured they were blue-green in colour – this being the natural colour of glass.
Clear, crystal-like glass was more valuable and rarer because it required additional processes to make it colourless. It is remarkable to find a dish, like the one in the Grosvenor Museum’s collection,  which has survived intact for nearly 2,000 years.
The Romans were efficient recyclers. A very useful property of glass is that it can be re-melted and re-used. So broken glass known as cullet was collected and melted down to supply new vessels and windows for Roman Britain. Thanks to modern methods of scientific analysis the origin of ancient glass can now be chemically identified.

Simon Malam, architect, Donald Insall Architects (Chester)
Glass has influenced architectural styles through the ages and for most of history has been a luxury item. 
Things really started to take off with the invention of drawn glass at the start of the 20th century (literally drawn through a machine). Glass became more economical and larger panes enabled new architectural styles to develop, characterised by the glassy buildings of the Modern Movement.
But transformational change came in the 1950s with the birth of float glass invented at Pilkington’s in St Helens. For the first time glass could be truly uniform and manufactured on a huge scale. Advances in engineering have seen glass used in structural ways, transforming buildings from insular spaces into the glittering glazed architecture we see around the globe.
As an architect specialising in new life for historic buildings, clever use of glass can be transformative. Looking forward, glass will play a large part in our journey to carbon-neutral. In ‘passive’ buildings glass will help capture solar gain and the latest leaps in thermal performance of glazing systems will reduce heat loss. The possibilities for the future uses of this transformational material seem limited only by our imaginations.  

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Jamie Moore, managing director, Recclesia Stained Glass, based at Sandycroft, near Chester
Anyone who has stood in front of a medieval stained glass window with its kaleidoscope of colours will have experienced its wonder and breath-catching beauty. Designed to illustrate biblical stories in a world where few people could read, the windows are not just beautiful but technically extraordinary. As experts in stained glass restoration, Recclesia Stained Glass has a front-row seat in their preservation and has restored Victorian glass projects such as the Grand Hall and staircase at Manchester Town Hall.
Now 150 years old, Victorian stained glass is starting to show its age. Natural deterioration through weathering, condensation, and pollution (from both inside and out) inevitably leads to failure of the leadwork and degradation of the glass surfaces and even the loss of paintwork. Our top tip for any work with stained glass is to step away from the window spray and call a trained conservation specialist. 
Pete Frost, director, World of Glass, St Helens
One of the greatest revolutions in glass since the time of the Roman Empire was the invention of float glass at Pilkington Glass in St Helens, Lancashire in 1959. For the first time, flawless, totally uniform, flat glass could be produced cheaply and in bulk and it quite literally opened up the world we know today – not just enabling glittering glass cityscapes but everything from the use of glass in spacecraft to the world’s computer and TV screens. 
The story of glass in St Helens is inextricably linked to the Pilkington Brothers glass company and its skill, ingenuity and decades-long perseverance in developing new glass processes. But the town itself contributed to the success of its leading industry being located on a coalfield, near Cheshire salt industry that contributed soda ash and a short distance from one of the world’s greatest ports, Liverpool. At the World of Glass, visitors have the chance of seeing live glass blowing, the priceless Pilkington Glass Collection as well as learning about industry in St Helens.  

Adrian Curry, MD, Encirc 
Glass is a wonderful, natural material. It is capable of being recycled an infinite number of times with no loss of quality. It is also one of the healthiest and most sustainable materials for storing food and drink. At Encirc, we see an incredible future for glass, which is why we opened one of the largest and most technologically-advanced bottle-making factories in the world on our 205-acre site at Elton, Cheshire.

To give an idea of scale of what we do, we make almost one in three of the glass containers used in the UK and Ireland today and Encirc’s Elton site is the only fully-integrated plant worldwide where different branded bottles can be manufactured, filled and distributed from one site.

Encirc’s Elton factory contains the two biggest container glass-melting furnaces in the world, and 14 bottle production lines. But Encirc will not rest on its laurels. As MD I am committed to leading container glass’s journey to net zero, as well as embracing the digitalisation of glass with blockchain technology.
Although our sodium carbonate flux does not come from Cheshire, I am proud of the role Cheshire salt played, and continues to play, in the story of successful glass making. It is a history of excellence and innovation Encirc is proud to continue.
I am also a keen supporter and board member of Glass Futures, the industry-led initiative in St Helens that will drive further glass innovation – not just in the North West and the UK, but worldwide. 

Aston Fuller, general manager, Glass Futures
Glass is almost infinitely recyclable and worldwide the glass industry makes the most of this property. However, the production of glass using sustainable, low-carbon processes is slow. Pioneering heat-saving on its huge gas furnaces, developing alternative manufacturing processes and robotics is difficult, challenging and expensive, even for multi-national glass producers. Sustainability and an environmental approach are every manufacturer's challenge, but how can it be achieved? 

The answer is to work together and to go big and bold. Due for completion at the end of 2022, Glass Futures’ 165,000-square-foot pilot plant, based in St Helens, will be a catalyst for this vital change. The not-for-profit organisation with no shareholders will be the first to open an open-access research and development glass plant in the world. 

By bringing together industry and academia it will stimulate ideas and foster close collaboration. More than this, for the first time, different technologies will be manufactured and tested in a full-scale batch plant, rather than on a small scale, vastly improving development timescales but also enabling the testing of more glass compositions and treatments. 

As Glass Futures’ Employee Number 2, I feel immensely privileged and proud to be part of pioneering green technologies such as biofuel technology; digitalisation and automation with the likes of existing partners Encirc, NSG Pilkington and Diageo. It also feels appropriate that this is taking place in St Helens with its illustrious glass history, as it will be from here that Glass Futures, through sustainable, low-carbon glass technology, will bring a cleaner and brighter future to a global audience.