Since someone has particularly asked, I'm typing in some stuff about Masamune. Most of the information is from Wiki but typing it out gives it a personal touch instead of just a link so here goes...
Masamune Okazaki , also known as Goro Nyudo Masamune (Priest Goro Masamune) was pretty much japans most famous swordsmith. Much mystery remains around his life and until today no valid date has been arrived at for his birth. The general consensus is that he
created swords in the 14th century from 1290 to 1350'ish.
As is known japanese katanas are broadly classified as Katana's, wakizashi's and tanto's (large, medium and small swords). Masamune's speciality lay within the Katana and Tanto. Together these were called daisho and the tanto was used for close hand to hand combat while the katana's reach was a little longer.
The interesting part was that Masamune gained fame in an era when steel was generally impure and where refining it took a lot of ingenius effort. Another interesting fact was that Masamune practically perfected the art of embedding crystals in the swod making it glitter. This art was called
Nie. His sword making style is specially known for a
distinctive grey lines on the leading edge (called chikei) and also
lightning like streaking along the blade (called Kinsuji). He did most of his smithery study under
Shintogo Kunimitsu.
Masamune's best works were signed with his name. The
Honjo Masamune which was the sword of the tokugawa shogunate passed down the generations is probably the most famous Masamune work.
Signed works of Masamune are rare. The examples "Fudo Masamune", "Kyogoku Masamune", and "Daikoku Masamune" are accepted as his genuine works. His swords are the most frequently cited among those listed in the Kyôho Meibutsu Cho, a catalogue of excellent swords in the collections of feudal lords, edited during the Kyoho era by the Hon'ami family of sword appraisers and polishers. The catalogue was created on the orders of the Tokugawa Yoshimune of the Tokugawa Shogunate in 1714 and consists of three books. The first book known as the Nihon Sansaku is a list of the three greatest sword smiths in the eyes of Toyotomi Hideyoshi including Etchu Matsukura Go Umanosuke Yoshihiro, Awataguchi Toshiro Yoshimitsu, and lists 41 blades by Goro Nyudo Masamune. Funny part is Masamune has more swords in that book than the other two put together!!! Talk about master smith eh?
