Urushi is a finish that has been used in East Asia for over 8000 years, and is waterproof, food-safe, and only susceptible to UV rays. Moreover, it gives an especially beautiful finish to surfaces finished with hand tools, showing off their facets and tool marks.
Yet, before curing, it will give contact dermatitis to those allergic, and so must be handled with care. Applied similarly to an oil, rubbed on and then buffed off, it must be kept in an environment of 60-80% humidity and 65-85 degrees farenheit in order to cure. A beautful finish not just for tablewares but for flat surfaces and carved objects like chairs and sculptures, I hope this finish is more broadly adopted in the West.