http://en.wikipedia.org/wiki/Thousand-year_egg

“Century egg, also known as preserved egg, hundred-year egg, thousand-year egg, and thousand-year-old egg, is a Chinese cuisine ingredient made by preserving duck, chicken or quail eggs in mixture of clay, ash, salt, lime, and rice straw for several weeks to several months, depending on the method of processing. After the process is completed, the yolk becomes a dark green, cream-like substance with a strong odor of sulphur and ammonia, while the white becomes a dark brown, transparent jelly with little flavour or taste.”

David S Community Contributor posted about 3 years ago