Nippon is the name for Japan in use before 1923, when the US government passed a law saying all goods from Japan must be marked "Made in Japan". Therefore, Nippon on a piece of pottery means it is at least 75 years old, and quite possibly could date to the previous century. The most famous maker is Noritake which is marked with an "M" inside a wreath. Other makers use a flower mark or just say "Nippon". They are all completely painted by hand. Value depends on size, maker (Noritake being very desirable) shape and beauty of the painting. There were several grades...a pink mark is lesser in quality than blue with a green mark denoting the highest quality. These are becoming less and less available as collectors snap them up. They truly do not make this quality of porcelain with the detailed hand painting any more.