My wife and I are renovating an old farm house using the original building materials, the main ingridient being clay, amongst other things. Yesterday I had just unloaded the mixer for the second time when I got the faint whiff of something not exactly nasal friendly but having the flu at the moment just couldn't pick up what it was. Half way through plastering the clay on the lounge room wall my sinuses cleared. CAT, not pee, POO My face happened to be about 10 inches from the wall at the time. We seem to have an over abundance of the "four legged fur balls"(not my favourite animal at the moment) in our area so I should have expected it. The amazing part is as the wall dries the smell lessens, or I'm getting used to it. Have I found a new Eco building material .......Kev