Photographs
Photographs by the seller at origin.
The piece
Katana by Koyama Munetsugu dated Tenpō 9 (1838), with an ubu tang and NBTHK Tokubetsu Hozon paper; presented in shirasaya, without mounts.
Koyama Munetsugu, a smith of the Koyama school working in Edo in the shinshintō period, consistently worked in the Bizen tradition. This katana has a nagasa of 71.8 cm and a sori of 1.7 cm; it is shinogi-zukuri with an iori-mune, wide and thick, with an extended chū-kissaki, and the photographs show a bōhi on both sides. According to the original seller, the jigane is a tightly forged ko-itame, almost plain, and the hamon is chōji-midare with some gunome, long thick ashi, a deep nioiguchi and touches of kinsuji and sunagashi; the bōshi runs straight with a ko-maru turn-back. The tang is ubu, with kurijiri, sujikai yasurime and a single mekugi-ana; it is signed 於東武固山宗兵衛宗次作之 (Tōbu ni oite Koyama Sōbei Munetsugu kore o saku) and dated 天保九年二月一日 (Tenpō ku-nen nigatsu tsuitachi), as the photographs confirm. The NBTHK certified it Tokubetsu Hozon Tōken in December 2025. According to the listing, it comes in shirasaya with a one-piece gold-plated habaki; it has no koshirae.
Strong points
- Signed and dated in the 2nd month of Tenpō 9 (1838)
- Ubu tang with a single mekugi-ana
- NBTHK Tokubetsu Hozon Tōken paper (2025)
- Bizen-tradition chōji-midare hamon, according to the original seller
- Wide, robust sugata with bōhi on both sides
Points to bear in mind
- Old polish: the original seller notes fine scratches, rubbing and light surface rust in places
- No koshirae
- The shirasaya is stated in the listing but does not appear in the photographs
Score
52.4 pointscurrent max. 255
-
Certificate
+50
NBTHK Tokubetsu Hozon paper +50
-
Tang
+25
Tang intact according to the seller at origin +25
-
Declared condition
−60
The original seller declares flaws 0 · minor flaws −10 · light red rust −50
-
Signature and date
+25
Signed and with an engraved date +25
-
Mounting
−15
No mounting −15
-
Blade
+10
71.8 cm: within the usable range +10
-
Shirasaya
+5
With a storage shirasaya +5
-
Price
+12.4
Price: the more affordable, the more points +12.4
The score adds and subtracts points for each feature of the piece and has no ceiling: the highest in the catalogue today is 255. It is computed from the record, not from an opinion. The mounting starts from what is known of its period, adds what vouches for it (its own NBTHK paper, a signed fitting, a crest) and subtracts what has been restored (saya, ito, same, habaki or sageo).
Measurements
- Nagasa
- 71.8 cm
- Sori
- 1.7 cm
- Tang
- Intact (ubu)
- Certificate
- NBTHK Tokubetsu Hozon
- Mounting
- No mounting
- Storage shirasaya
- Yes
- Smith
- Koyama Munetsugu
- Period
- Shinshintō (1781-1876)
- Dating
- 2nd month of Tenpō 9 (1838)
- Province
- Musashi
- Mekugi-ana
- 1
- Condition
- Minor flaws declared
- Signed
- Yes
- With an engraved date
- Yes
- Motohaba
- 2,9 cm
- Sakihaba
- 2,1 cm
- Motokasane
- 0,75 cm
- Sakikasane
- 0,5 cm