NTHK

Authentication certificate for Aoe school blades; formal attribution to this Bitchu Province tradition.

Colloquial Western term for Koshu Tokubetsu Kicho papers, which had a blue cover. Unlike green/white papers, blue papers were issued by the central NBTHK authority in Tokyo, not the provincial branches where authentication scandals occurred. More reliable than other Kicho-era papers but still not up to modern Hozon standards in rigor. See: koshu-tokubetsu-kicho.

Attributed to; traditional attribution without certainty.

Old attribution; historical sword appraisal or authentication, often from earlier periods.

Art name or pseudonym used by smiths and artists; also the name given to a celebrated sword (e.g. Heshikiri Hasebe).

Colloquial Western term for Tokubetsu Kicho papers (pre-1982), which had a green cover. Treat as equivalent to no papers—approximately 95% of attributions are unreliable. Exception: low-value fittings from inexpensive schools where modern Hozon certification costs exceed the value gained. See: tokubetsu-kicho.

Box inscription; writing on a storage box identifying the contents, often by a recognized authority, used as authentication.

The most prestigious family of sword appraisers, active from the Muromachi period through Edo. Their origami certificates remain highly valued.

Deferred judgement; a status given by NBTHK shinsa when a blade cannot be definitively attributed or authenticated. The item is held for further study rather than being passed or rejected. Blades with horyu status may be resubmitted after additional research or restoration work.

Measurements; the dimensions section (nagasa, sori, widths and so on) of a sword's appraisal description or catalogue entry.

Worthy of preservation; NBTHK certification indicating a blade meets standards for historical and artistic value.

Important; NBTHK designation for blades and fittings of exceptional quality, ranking below Tokubetsu Juyo.