Assertion: tachi blade | /r/HasProperty | converted into katana
Facets:
value: in the late 1500s
type: TEMPORAL
value: in early 1600s
type: TEMPORAL
Source sentences:
text: In the late 1500s and early 1600s many old surviving tachi blades were converted into katana by having their original tangs cut (o-suriage), which meant the signatures were removed from the swords.