Air Drying Clay & Environmental Concerns
At Hot Clay, we have always had reservations about selling traditional air drying clay, which is why we chose not to stock it.
There are generally two types of air drying clay available. One contains a gypsum-like ingredient that will cure and harden like plaster. The other, which is the type we are particularly concerned about, contains synthetic fibres, which are usually nylon-based.
Our concern has always been less about how the material performs in use, but more about what happens at the end of its life.
Why This Matters
Air drying clay is widely used in educational settings, seasonal pottery groups, and outdoor creative activities. These are all brilliant entry points into making and should absolutely be encouraged.
However, the nature of many of these projects means the results are temporary. Pieces may be discarded over time, broken down outdoors, or simply not retained long-term.
One example that became popular was “seed bombs”, where seeds are mixed into clay and scattered into the environment. With normal clay, this is less of a concern, but when clay bodies containing synthetic fibres are used, those fibres are effectively introduced into the wider environment as the clay breaks down.
There are, of course, many responsible and long-term uses of air drying clay in sculptural and artistic practice, where work is intended to last and remain indoors for years. Our concern has always been focused on disposable or short-life applications rather than these established artistic uses.
Looking For A Better Approach
Over the years, we have tried to encourage manufacturers to consider more environmentally responsible alternatives, but progress has been limited and change within the category has been slow.
As a B-Corp company, we try to take a more considered view of the materials we sell and prioritise options that reduce environmental impact wherever possible. Rather than waiting for a wider industry shift, we decided to explore alternatives ourselves.
We have spent time testing various materials and possible substitutions, and we eventually opted for a cellulose-based fibre that is not only biodegradable but could also provide the same functional benefits without relying on synthetic nylon fibres. This became the foundation of our Vitraclay Air Drying Clay.
Finishing & Decorating
As previously mentioned, Vitraclay Air Drying Clay uses biodegradable cellulose fibres, which provide additional engineering strength while the clay dries, helping to reduce cracking, improve handling strength, and to support larger or thinner pieces during the drying process.
Once dried, you can then seal the surface of your ware with a mix of PVA glue and water. Allow this to dry, then decorate with household paints or, more commonly, acrylic paints.
It's important to note that the cellulose fibre remains stable while stored inside the clay body because it exists in an anaerobic environment. However, as with all clay products, we recommend storing in a cool, dark place, keeping the bag sealed when not in use and using the clay within a sensible timeframe. It is important to note that biodegradation relies on the presence of moisture. Once a piece has been fully dried and sealed, it becomes stable for normal indoor use and does not continue to break down in that condition.
