Fired test bars of Park Royal clay, each stamped with its batch number.

CERAMICS / CLAY

Park Royal Clay

The goal: turn clay dug from a Park Royal construction site into a usable casting slip, and map how it behaves when fired.

As it comes, the clay would not slip-cast. Every sodium deflocculant tried did nothing or gelled it. Adding 2.5% barium carbonate made it fully suitable for slip casting.

Firing tests across 700 to 1150 C show where it matures. The results are being published openly as they develop.

See the cup made from this clay.

See the findings

If you have a London site with excavated clay or other waste, your material could be an input. We test clean local clay and site waste in small documented quantities, and share what we find.

Talk to us about your site waste

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