T197.  Iron sukashi tsuba signed Bushu Ju Masakata.  7.1 x 7.3 x .4 cm.  The nakago hitsu-ana is .8 x 2.5 cm.  Masakata was the 3rd generation head of the Bushu Ito School and son of Bushu Ito Masatsune.  His date of death is 1774.  This is a very nice tsuba in excellent condition.  The theme is 4 rings, referring to an aspect of swordsmanship: being able to defend in 4 quadrants at once.  $500.