 Martin of Bohemia, on his 1492 geographical globe, located the islands of Chryse and Argyre ("Gold" and "Silver") in the vicinity of Zipangu (Japan), which was said to be "rich in gold" by Marco Polo.An expedition was sent to find the purported islands in this location under the command of Pedro de Unamuno in 1587.The names of various geographical features and settlements of the Golden Chersonese are given in "Ptolemy's Geography", including towns and rivers.