I think the piece is from chinese immigrants, it was also found with what appears to be Native American Indian pottery. The piece is old and the porcelain is hand made with a fine white clay and crushed stone.
Feb 23, 2010
mark on shard by: Peter
Hi, The angle and resolution of the image makes it difficult to decipher the second character. The first one would be read "zheng" in Chinese, but it is also very frequently used in Japanese names. Actually, there are only few marks in antique Chinese porcelain that start with the first character. Therefore, I would rather think the mark is a Japanese potter's mark. The foot ring of this shard also isn't typically Chinese, or it is quite new.