Sort your waste at the source
Recycling clay only works if you sort as you work. Mixing bodies, or mixing glaze into clay, produces material that is useless and has to be discarded. Three buckets, clearly labelled, solve most of the problem.
- Bucket 1Clean throwing water — reused for throwing
- Bucket 2Bone-dry trimmings and scraps of one known body
- Bucket 3Glaze rinse water — never mixed with clay
Clay sets hard inside pipes and blocks them permanently. Glaze solids do the same, and they carry metal oxides into the water system. Let everything settle, and dispose of the solids as solid waste.
The reclaim process
Reclaiming is the process of turning dried scraps and settled slurry back into workable clay. It takes a few days of passive waiting and about twenty minutes of work.
Dry and break up the scraps
Let trimmings and failed pots dry completely, then break them into small pieces. Dry clay slakes faster than damp clay.
Slake in water
Cover the dry scraps with water in a bin and leave them for a day or two until they break down into a thick slurry.
Mix to an even consistency
Stir thoroughly with a powerful drill mixer or a sturdy paddle until there are no lumps. Consistency should be like thick cream.
Spread to dry
Pour the slurry onto a plaster bat or a porous board. The plaster wicks out water and the slurry stiffens into workable clay.
Wedge and store
When it reaches throwing consistency, wedge it thoroughly — reclaim is often short and needs working. Store in sealed bags and label with the body name.
Reclaimed clay is often slightly shorter and less plastic than new clay. It is excellent for slab work and hand-building, and can be blended with new clay for throwing.
Handling glaze waste
Glaze rinse water is not the same as clay slurry. It contains metal oxides and fluxes, and it should never be poured away or mixed into clay. The correct handling is settling, decanting and disposal of the solids.
- Collect all glaze rinse water in a dedicated settling bucket — never the sink.
- Let it stand until the solids settle and the water on top is clear.
- Decant the clear water (it can go down a drain, or be reused for cleaning).
- Let the remaining sludge dry completely in a tray.
- Bag the dried sludge and dispose of it as solid chemical waste, not as household rubbish.
Before discarding a settled glaze, check whether it is simply dried out. Add water, sieve it and test it. Most "dead" glaze is just dehydrated.
Keeping dust out of the air
The waste you can see is the easy part. The waste that matters is the dust you cannot see. Every handling step in reclaiming — breaking dry scraps, emptying bins, mixing slurry — is a dust-generating event.
- Break dry scraps inside a bin or under a damp cloth to contain the dust.
- Wear a P100 respirator when emptying bins or mixing dry material.
- Wet-mop the floor and wipe benches with a damp cloth at the end of every session.
- Never use a standard vacuum. If you use one at all, it must be HEPA-filtered.
- Keep the studio floor free of dried clay. Walking grinds it into airborne dust.
Reclaiming saves money, but the real reason to do it is that clay and glaze are the two materials most likely to end up in a drain or a landfill from a pottery studio. Sorting them correctly is simply what competent studio practice looks like.
Ceramic work involves respirable crystalline silica, kiln temperatures up to 1300 °C and glaze materials that can be toxic in powder form. This guide is an educational reference — it is not a substitute for the instructions supplied with your equipment. Always ventilate, wear appropriate respiratory protection when handling dry materials, and read our studio safety guide.
