YAKUMO JAPAN

Makers · 作家 · Tokoname

Zengo

銭号

Recorded in 2006 as one of the kilns that have been making bonsai pots in Tokoname the longest. Its proper name is the Izumiya kiln; Zengo is a nickname, and it comes from a misreading of the mark. The mark itself is a misreading of a different kind — it is Chinese, and it was copied.

A Zengo pot, an unglazed grey rectangle
Rectangle, unglazed.

At a glance

Trade name
Zengo 銭号 — a nickname
Proper name
Izumiya kiln 和泉屋窯
Workshop
Izumiya pottery 和泉屋製陶所
Potter
松下益久
Region
Tokoname 常滑
Standing
Among the oldest bonsai-pot kilns in Tokoname
Body
Almost entirely unglazed
Clays
Shidei chiefly, and Tokoname udei
Moulds
An old kiln, so a deep stock of forms

01 · 落款 The mark

A Chinese mark on a Japanese pot

This is the thing to know before you buy.

The mark documented for the kiln reads 銭子窯製. It began as the mark of a Chinese pot of the middle import period. Before the war, when Tokoname kilns were making copies of Chinese ware, they copied the mark along with everything else — and this one stayed. 秘色窯 is named as another Tokoname example of taking an old Chinese kiln name as one’s own.

So the mark is not evidence that a pot is Chinese. It is a Tokoname kiln’s mark.

The mark is not evidence that a pot is Chinese.

02 · 通称 The nickname

Why anyone says Zengo at all

The mark is in seal script, and in that script the character 子 can be taken for 号. The nickname settled from that misreading, and the trade has called the kiln Zengo since.

The conclusion drawn is a reasonable one: a kiln picking up a nickname at all is taken as a sign of how well known it was.

One more name to keep straight. There was a second Izumiya pottery in Tokoname, the 松萱窯. As of 2006 it had suspended pot production.

03 · 実物 The mark on a pot

A square seal in relief on the base of a pot handled as Zengo

A square seal, the characters standing proud of the clay.

A square seal, raised, in seal script

On the base of a pot handled by us as Zengo. A square frame with the characters raised rather than sunk, in seal script.

This is the shape of the thing that causes the confusion. A square seal in seal script, on an unglazed clay pot — and it looks like that because it was copied from the mark of a Chinese pot.

The mark recorded for the kiln is 銭子窯製, a square stamp in seal script.

04 · 実物 A second pot, a second observation

A square seal in relief on the base of a red unglazed rectangular pot handled as Zengo

Red clay, unglazed. A 15.2 cm rectangle.

The same square seal, on red clay

Photographed on 11 November 2026 on the base of a second pot, a 15.2 cm unglazed rectangle in red clay, a different clay from the grey pot above. The kiln is recorded as working chiefly in shidei; this pot is shudei, which is what we observed.

The form matches the first example: a square stamp, the characters raised, in seal script, set in two columns of four. Two pots is two observations, not a rule. We record what we have seen and do not say that this is the only form the kiln used.

05 · 落款 The mark

One documented form

A square stamp in seal script. This is the form currently documented here for the kiln; it is not a claim that the kiln used no other.

Mark Reading Note
銭子窯製A square stamped mark in seal scriptOriginally the mark of a Chinese pot of the middle import period, copied before the war and kept.

A mark is not a passport

Do not read this mark as proof of Chinese origin. The record states plainly that it was copied from Chinese ware by Tokoname kilns.

06 · 土目 The clays

Shidei, and the smoked black

The kiln works almost entirely unglazed, and being an old one it has a deep stock of moulds. The clay is chiefly shidei, the purple-brown zisha.

The other one is worth learning. Tokoname’s udei is called イブシ, ibushi, locally, and the point made about it is that it looks settled straight out of the kiln — a new pot that does not look new.

Sizes run from small to large. As of 2006 the small and mid sizes were the ones in demand.

07 · 代表作 Recorded works

Recorded works

Not for sale — seven pots recorded for this kiln, in three entries. The first two entries are sets of three.

Work Size (cm)
Udei rectangle, outer rim, indented corners — one of a set of three in nearly the same form and much the same size. A set like this lets you match a pot to a tree by fine degrees15.5 × 12 × 6
Udei rectangle, outer rim, indented corners — the second of that set18.5 × 14 × 7.5
Udei rectangle, outer rim, body band — the third19 × 14.5 × 6
Shidei rectangle, outer rim, indented corners — the first of a second set of three, in a quieter clay than the set above. Sets in one form and several sizes exist too, and they are useful19 × 14.5 × 5.5
Shidei rectangle, everted rim — the second19 × 14.5 × 6
Shidei rectangle, body band, rounded corners — the third19 × 15 × 5
Udei mokkō, outer rim — mid size. The outer rim looks strong with the pot on its own, and stops looking so once a tree is in it; the form takes more than you would expect. Not for the formal manner — an upright trunk, or a thick trunk with a quiet figure — but right for something a little more relaxed40 × 33 × 13

Available

Zengo pots in the collection

Each pot ships worldwide from Tokyo.

Send us a photograph of the underside and we will tell you what the mark says — and, with this kiln, what it does not mean.