Down to earth: Why more potters are making use of wild clay

From mushrooms foraged in woodlands to succulent samphire from the coast: if you’ve visited an upscale food market or trendy restaurant in recent times, you’ll have noticed the rising popularity of ingredients that are local and unstandardised. It’s hardly surprising; we are all increasingly aware of the carbon footprint involved in packaging, processing and shipping produce worldwide, and of the perils of global supply chains (as I write, Britain’s supermarket shelves are bare of tomatoes, due in part to bad weather in Spain).

As many in the wealthy western world try to eat more food sourced from their local area, parallel preoccupations are appearing in the craft sphere: from carpenters sourcing wood from nearby forests to potters choosing to use clay dug up close to home. This latter approach is niche, but rising rapidly in popularity – as a new book, Wild Clay: Creating Ceramics and Glazes from Natural and Found Resources (Bloomsbury Publishing), makes clear.

Written by potters Matt Levy and Takuro and Hitomi Shibata, it’s a guide to sustainably sourcing, processing and using wild clay, alongside a showcase of work by international ceramic artists who dig their own raw materials. The title marks a turn in the tide – a change in how ceramicists and their audience think about their craft, and in the values they seek to uphold. When it comes to sustainability, working with fired clay comes with inherent challenges: from carbon-heavy kiln firings and sometimes-noxious glaze ingredients, to the footprint of mining and shipping virgin materials across the globe. With that in mind, many potters are increasingly keen to lighten their environmental load (see ‘Costing the earth’, Crafts no. 284).

Levy draws explicit parallels with food. Using processed clay is ‘like cooking from a prepared meal kit where you simply follow the given instructions and everything you need comes from a bag’. In contrast, Hitomi Shibata compares working with wild clay to ‘growing heirloom vegetables in the garden for our table’. And, as anyone who gardens will know: ‘There is a lot of waiting time. There might be many mistakes and false starts.’ This is because of the sheer unpredictability of the task: no two dig sites are the same, and the chemical composition of clay can vary from batch to batch, even when sourced from the same location, requiring patient rounds of testing. You also need flexibility and imagination: a clay that proves unusable for throwing, say, may be ideal for use as a decorative slip.

First up: a definition of terms. ‘When we use the term “wild clay”, we are speaking about clays that are not commercially available [and processed in a factory]. All clay, after all, is indigenous to our planet,’ write Dean Adams and Josh DeWeese, co-directors of the International Wild Clay Research Project, in the book’s foreword. ‘Commercial clays provide consistency and have been vetted by others. Local clays offer unique colours and other qualities a specific artist might desire in their work.’ Their material and visual properties are myriad. Found clays can contain inclusions – small pieces of stone or grit that create ruggedly textured surfaces. Thanks to varied mineral makeups, their colour palette can range widely: everything from rich, dark reds, soft pinkish tones and sulphurous yellows, to greys, blacks and whites. For potters such as Nina Salsotto Cassina, who works under the name Unurgent Argilla, this rich range provides endless inspiration. The Milan-based maker repeatedly throws the same spherical form, varying only the wild clays used, which she digs from locations across Europe.

Needless to say, wild clay is not a new discovery. For most of human history, potters worldwide have used materials found close to home; all clay was necessarily wild. What is new, relatively speaking, is our detachment – geographical, practical, intellectual, emotional – from these raw materials, as they have become available through large-scale retailers in a more standardised and sanitised form. It’s a detachment that a new generation of ceramicists are working to undo, enjoying wild clay’s material properties and – let’s face it – the sheer romance of digging it yourself.

The potter Anne Mette Hjortshøj is emblematic of this revival. Working from her farm-based studio on Bornholm, a Danish island in the Baltic Sea, Hjortshøj processes a rich variety of clays herself, sourced from the coastline. She uses these to create tactile tableware: from bottle-vases to bowls, the palette of each piece echoes the land from which it came – subtle grey-greens recall wintry woodlands; off-whites are reminiscent of trodden snow. Until recently, the island was home to a thriving ceramics industry, thanks to its abundance of clays. ‘Within 10 kilometres from where I live you can find everything: low-firing clays, high firing clays, different colour clays, rocks for making glazes,’ she says. This remarkable bounty is the focus of the Bornholm Wild Clay Research Project, made up of Hjortshøj and a handful of fellow potters working between the Danish isle and Mashiko, Japan – another corner of the world where wild clay has long been part of everyday life.

To harvest her materials, the potter first seeks permission from the relevant landowner, before she and her husband take a small boat along Bornholm’s coast. Here, they travel along an ever-changing cliff face of layered clays, eroded by the crashing waves by up to half a metre a year. After filling the boat with their finds, she returns to her workshop, where she lays out the clay to dry in the sun (‘It’s a summer job’). She then breaks it down into powder, mixes it with water and leaves it to soak for a week, before passing it through industrial-sized sieves. Finally, she lays the clay out on an absorbent surface to dry a little before storage. ‘It’s very time consuming to do it yourself. But it’s not so difficult to clean it up and make something from it,’ she says. Having a gallerist take care of the commercial side of her business – her pots are sold exclusively through Goldmark Gallery – means she has time to work in this slow way, which has become intrinsic to her aesthetic. ‘The more you work with local clays, the less you can go back. The variety of clay I use has become a big part of the identity of my pots.’ Hjortshøj has stockpiled eight stoneware and two earthenware clays, which she mixes into blends suited to different parts of her wood-fired kiln. Acting as a foil to her slips and glazes, these clays create surfaces with depth and richness.

It has also become part of her own identity. As a transplant to the island, she sees her ‘journey into becoming a local citizen’ enhanced by working closely with the land. There are, of course, ecological benefits to working this way: no heavy bags of plastic-wrapped, processed clay needlessly wending their way around the world. Over the pandemic years, Hjortshøj appreciated her self-sufficiency – no issues with imports and disrupted supply chains from China for her.

It’s not all rural romanticism, however. The London-based ceramicist Alison Cooke sources clay from the capital’s construction sites – the city is built on deposits dating back about 56 million years – for pieces such as her Thames Clay Vase; its tubular form is extruded using a smooth and vibrant orange clay. Its industrial-chic shape nods to the tubes and tunnels that undergird the city, while each vase is stamped ‘London Clay, Depth 26m’: a reminder of the deep borehole this material came from. Fittingly, the edition of 30 is sold through Atelier100, a collective designed to promote work made within 100km of central London.

The clay was sourced during the digging of the Thames Tideway Tunnel, better known to the public as the Super Sewer; for other projects, she has used clay from sites such as London Bridge station. ‘I’m interested in the location before I’m interested in what I’m going to make,’ she tells me. ‘The provenance of the clay gives it something special.’ That’s just as well, as it turns out this particular material is ‘horrible’ to work with. ‘It’s a beautiful rich colour, but it’s very sticky and gloopy. It’s like trying to wedge porridge and Blu Tack.’ For better or worse, Cooke has five tonnes of the stuff to get through – five tonnes being the minimum she could get from the building site. It came free, but costs came from admin time – trying to convince baffled bureaucrats to grant access – and in transportation, processing and storage.

It’s not always this hard. ‘Anyone who wants wild clay in London can find a construction site – when you see those piling machines that look like corkscrews, you know they’re digging deep for foundations.’ Cooke generally just knocks on doors and asks to fill a bag. ‘If you see someone’s having a basement dug out, that’s a nice opportunity.’ Upmarket parts of the city like Mayfair are good for that, she adds.

On the other side of the Atlantic, Studio Alluvium – a duo made up of ceramic artists Mitch Iburg and Zoë Powell in the city of Saint Paul, Minnesota – are also using the clays and minerals native to their state, which they explore with the help of geological maps. Alongside their work as individual artists, their mission includes research, education and partnerships to promote the use of wild clays. In the process, they hope to ‘build community and connection to the earth’. Though they dig the same clays, their work is not similar: Powell creates smooth, cellular-looking artworks, while Iburg makes rugged vessels, tableware and sculptures – demonstrating the variety of effects that wild clay, in all its diversity, can create. As they tell the authors of Wild Clay: ‘Our responses to their properties are often very different. By blending clays and adding or removing aggregate, we each personalise our own clay bodies to serve as the foundation of our work.’

While many gravitate towards wild clays for their material qualities, for others it’s their poetic charge – their symbolic potential – that draws them in. During the dark days of the presidency of Donald Trump, when political divisions in the United States reached a painful pitch, Los Angeles-based potter Adam Silverman began his project, Common Ground. The idea: to gather clay, water and wood ash from each of the country’s 50 states, plus Washington DC and the five inhabited US Territories (Puer to Rico, the US Virgin Islands, Guam, American Samoa and Northern Mariana Islands). The idea was to mix these together to symbolise the undoing of cultural divisions and the creation of a new unity.

Following his call-out for help on social media, supporters star ted sending him these materials through the post: ‘A couple of people sent dir t by accident. It was a leap of faith to mix them all together.’ Once he had collected them all, Silverman made a set of 56 plates, bowls and cups, alongside 56 ‘ceremonial vessels’. The standardised tableware shows the influence of Japan’s great ceramic traditions with a yunomi-like beaker and a rugged finish, while each vessel is unique: ear-like lugs protrude from lumpen, scarred bodies. Though embattled, their tops are open, receptive: a clear symbol of the body politic. Their making was, of course, only possible following a long process of mixing and cleaning, and testing different temperatures, kilns and ratios of clay to ash. ‘It could have been a total failure, for sure, but it worked out quite beautifully – supporting the metaphor that integrating diversity is a positive, not a negative.’

Working with professor and activist Scott Alves Barton, he now organises meals for 56 people at a time, at a variety of locations around the country. The aim: to bring different participants around the table for the shared experience of dining, with the table settings acting as an elegant conversation-starter. ‘It’s not about me,’ Silverman says. ‘It’s about the project being a tool to bring people together.’

At a time when ecological anxieties and social divisions are hitting hard, these gestures – however humble they may be – are undeniably heartening. As Hjortshøj puts it: ‘Sometimes I think maybe I should stop making pots and start working with willow or recycled materials, but I won’t do that. I will keep making pots, having found my own little way of not hating myself too much by not importing so much plastic-wrapped clay.’ So long as mass-produced ceramics remain the norm, choices made by studio potters won’t erase industrial-scale clay mining, processing and shipping from existence. Yet, as the saying goes: every little helps.