To document completion of the BB, provide proof of the following:
- Plaster with earthen plaster
- Include drain pipe and plumbing/faucet
- Oil with drying oil (linseed, tung, hemp, etc) and burnish till glossy
- When dried, it must hold water overnight without becoming soft or muddy
- Provide images of your process, stages of the build
- Provide video of inspecting the sink after holding water for a minimum of 12 hours. Show edge details, show that water has NOT seeped under or into the sink body.
Sure, I think the key to this one is making the sink from cob, making it waterproof and having it be completely non toxic. If you come up with another way, we'll very likely approve it. Or if you suggest a clear re-wording of the BB that includes your intended process, we can tweak it now.
"Hundreds of years from now it will not matter what my bank account was, the sort of house I lived in or the type of car I drove... But the world may be different because I did something so bafflingly crazy that it becomes a tourist destination"