In Cold Heart, Yamabuki finds an armor maker to repair a gash to her chest protector. Japanese armor was solid, but unlike the kind of armor seen in The Game of Thrones, it was not plate. Part of it were made of steel pieces called kozane and other parts were lacquered leather. Much of it was tied together by silk cords of vivid colors thanks to the perfection of silk dying in Japan. The armor was light, which allowed the warrior to move, and heavy enough to withstand arrows.
Not every part of the armor was metal.
The upper part of this kind of armor is pictured below.