In Part 1 of this post, we traced the path that chasan and tenmoku took from Song Dynasty China to Muromachi Era Japan—the era in which these bowls became formally categorised and described, employing the terms that we still use today.

In this part, I’ll break down these categories and how their cultural value has changed over the centuries. 

Types of Tenmoku

Over the thousand years since tenmoku first arrived in Japan, they have been given various names and classifications. Here I’ll outline the main historical classifications as well as how these definitions have shifted over time.

The Source: Kundaikansōchōki

Fig. 1: Tea Shelf Arrangement from a 1512 copy of the Kundaikansōchōki

At the end of Part 1, I introduced the grandfather and grandson pair of Nōami and Sōami: two of the aesthetic advisors (dōbōshū - 同朋衆) to the Ashikaga shōguns, with a specialisation in tea. Together, they outlined the appraisal, ranking, and formal display protocols for imported Chinese artworks, including paintings, incense burners, and tea bowls. 

Many of their teachings are recorded in the Kundaikansōchōki (君台観左右帳記): a supposedly secret text that was likely compiled by Sōami which outlines how to appraise and display karamono (唐物 - imported Chinese art pieces) in the Shōgun’s palaces. Written some time in the late 1400s–early 1500s¹, the text contains evaluations of Song Dynasty paintings held by the shōgunate, detailed diagrams for how to arrange display shelves, guides to identifying chaire shapes, but most importantly for us here, a section classifying and ranking tenmoku.

This formerly secret text was later copied, sold, recopied, and published hundreds of times following the Ōnin wars and the subsequent sale of many of the Ashikaga Shōgunate’s collection of karamono treasures². Not only did the proliferation of this text make it more accessible for researchers today, but it also disseminated and popularised Nōami and Sōami’s names and classifications for tenmoku, which became the basic standard that we still use today³.

At last, using Sōami’s original classifications, I can finally introduce the different types and categories of chasan and tenmoku. So let’s go through these one by one in decreasing order of value according to Sōami:

Yōhen (曜變・曜変) 

Fig. 2: Fujita Yōhen Closeup

Sōami has this to say about Yōhen:

Yōhen: The most exquisite of the kensan. It is unlike anything else in the world. The base is pure black, with dark and light lapis lazuli stars scattered throughout. There are also a variety of colors, from white to dark to lapis lazuli, resembling brocade. Worth 10,000 rolls of silk.

Converting barter amounts from the late 1400s into modern-day currency is...difficult impossible, but regardless, 10,000 bolts of silk is a lot, especially in the 1480s when silk was hand-spun and hand-woven. In any case, these bowls are treasures that were considered the pinnacle of Jian ware, with a stunning iridescence likened to the wonders of the cosmos.

Yōhen (曜變), written a few different kanji combinations⁴, roughly translates to “Celestial Glittering Transformation”, which, apart from sounding like a spell from a Magical Girl Anime, is a pretty apt name. It is likely a play on the word yōhen (窯変) which is a common term in Japanese pottery, which means ‘changed or transformed in the kiln’. Today, they are most commonly called 'yōhen tenmoku chawan', but as you’ll see shortly, this goes against the way these bowls were conceptualised in this time.

Using Sōami’s description, a few bowls have been described as yōhen over the centuries, some owned by the most famous figures in Japanese history subsequently lost to time…or fire. Today, only three survive, each one designated a National Treasure and each beautiful in its own way.

Inaba Yōhen

Fig. 2: Inaba Yōhen, Seikadō Bunka Museum

Diameter: 12.2cm
Height: 7.2cm
Foot: 3.8cm wide, 0.55cm tall
Weight: 284g

The most famous of these is the Inaba Yōhen, currently housed at the Seikadō Bunka Museum in Tokyo. It was owned by the Tokugawa Shōgunate who gifted it to the Inaba family in the 1600s, who sold it to the Iwasaki family in 1918, who eventually gave it to the museum. It is often considered the finest of the three surviving yōhen, and was second only to the one owned by Yoshimasa and Nobunaga that was subsequently destroyed.

This bowl has a perfectly balanced shape with a glaze that is a deep-blue black on the outside. However, the inside is where the magic is: its large silvery spots are outlined in a glowing silver halo that stands out from the backdrop, which itself is a brocade of blues and greens that shift with the light.

Fig. 3: Inaba Yōhen on Amagasaki-dai

Today it is paired with a Song Dynasty Amagasaki lacquer dai, with a warm brown hue and gilded rims.

At the museum gift shop, you can buy all sorts of yōhen merch, from scarves, to tea shirts (pun intended), to pins, and the often sold out plushie. We don't have the plushie, but we do have the gorgeous tenugui. If you want one, you don’t have to go all the way to Tokyo, you just have to click here :)

Fujita Yōhen

Fig. 4: Fujita Yōhen, Fujita Museum

Diameter: 13.6cm
Height: 6.8cm
Foot Diameter: 3.6cm

Next up is the Fujita Yōhen at the Fujita Museum of Art in Osaka. The oldest known owner of this bowl was the first Tokugawa Shogun: Tokugawa Ieyasu himself⁵ (1543-1616). Ieyasu gave it to his 11th son and it was passed down through his branch of the Tokugawa family until it was sold in 1918 to the Fujita family, who then transferred it to their museum upon its founding in 1951.

Compared to the Inaba, the Fujita has a slightly wider, flatter shape, and a darker, more subtle beauty. Lacking the silvery halos, the spots appear like dark voids in a sea of iridescent blues and greens that shimmer with vertical lines like the aurora. Tea Ceremony Researcher Yabe Yoshiaki has said, “compared to the sublime beauty of Inaba Tenmoku, this bowl is based on a ladylike grace."

Fig. 5: Fujita Yōhen on Ming Dynasty Mother of Pearl Dai

This bowl features a common addition found on surviving tenmoku in Japan: a fukurin (覆輪 - cover ring⁶). This is a band of silver, gold, or copper that encases the rim of the bowl. Not only does this protect the rim from chipping, but sometimes the rim of these bowls can be a little sharp and rough, so the smooth metal makes for a nicer drinking experience. 

Fukurin were a common design trend across multiple styles of Song Dynasty ceramics, not just Jian ware. While some tenmoku that remain or were unearthed in China also possess fukurin, they are of a slightly different construction, material, and design than those found in Japan, suggesting that the Japanese examples were applied locally, perhaps replacing or repairing previous fukurin. In China, most fukurin were tin or silver, but Japanese examples often use gold or gilded brass in addition to the whiter metals.

The Fujita Yōhen is paired with a gorgeous mother of pearl inlay dai, probably made in the Ming Dynasty in China.

Ryōkō-in Yōhen

Fig. 6: Ryōkō-in Yōhen

Lastly, we have the Ryōkō-in Yōhen, housed at Ryōkō-in, a sub-temple of Daitoku-ji in Kyoto. Its oldest attested owner was famous teaist Tsuda Sōgyū (津田 宗及, ???–1591) before it was eventually passed to Ryōkō-in at its founding in 1616, where it has remained since.

This is the most mysterious of the three, partially because it is not regularly open to the public and is rarely seen, but also because its beauty is also more dark and mysterious. Unlike the vibrancy of the Inaba and the depths of the Fujita, this bowl is much more understated. It is the smallest of the three and at first appears dark, plain, and unassuming. But under the light the silvery spots appear and the deep blue begins to shine and it is incredibly intense in the halos around the spots. The outside also is a deep beautiful blue, struck though with cracks and crazing unlike any other yōhen.

Hangzhou Fragments

Fig. 7: Fragmentary Yōhen unearthed in Hangzhou

Part of the mystery and beauty of yōhen bowls are their rarity. How are there only 3 in the world and why are they only in Japan if they were made in China? One theory was that the rainbow iridescence was considered unlucky in China and all other yōhen were destroyed. In 2012, it was revealed that fragments of a yōhen kensan were discovered in Hangzhou in 2009 along with other ceramic shards belonging to members of the Song imperial court, suggesting that they did use and treasure these bowls as well. 

While some doubt the authenticity of these shards (see below for more about fake tenmoku), the current scholarly consensus is that they are real. Compounding this was the discovery of another yōhen shard in Hangzhou more recently in 2023 and the rediscovery of one unearthed in 2000. These shards are in private ownership and are still being studied, with no published findings yet available.

As to why all of the intact bowls are in Japan and none are in their country of production, it is thought that the shift in style from whisked tea to steeped tea in the Ming Dynasty, rendered all chasan (and thus yōhen) obsolete and unfashionable. As mentioned in Part I, the bulk of the chasan in Japan were old, used antiques shipped from Yuan or Ming China in the 1300s, rather than transmitted directly from Song China a few centuries earlier during the height of their popularity.

Nobunaga’s Lost Yōhen

While only three intact yōhen remain in Japan, historical records point to the existence of at least one more: the yōhen owned by Ashikaga Yoshimasa and handled by Nōami. This bowl was one of the treasures of the Ashikaga Shogunate, a collection often called the Higashiyama Gomotsu (東山御物). This bowl passed into the hands of unifying warlord Oda Nobunaga, who supposedly used it on the night of his death during the Honnō-ji Incident. It is generally assumed that this bowl was lost and destroyed in the ensuing fire, although some claim that it is still out there. This bowl was considered the most exquisite of the yōhen and is probably the one that Nōami used to name and define the category.

Other Yōhen

There are a handful of other tenmoku that have been called yōhen over the years, either in historical records of tea gatherings or in tea bowl appraisal books. Many of these have been passed down to famous museums and institutions, such as the Nezu, Tokugawa, and Miho museums. While they are stunning bowls, they are today usually classified as exemplary yuteki, falling short of the name yōhen.

Lost Treasures or Fakes?

Fig. 8: ‘Lost Yōhen’ as featured on NHK in 2020, sold in 2021

There are two famous instances of recently discovered bowls touted as potentially being the ‘lost fourth yōhen’. The first, and least believable, appeared on an antiques appraisal TV show on NHK where it was valued at 25 million yen (~$200,000 in 2016). A contemporary Chinese ceramicist later revealed themselves as the maker, saying that the bowl was made as a cheap souvenir, sold for the equivalent of a few thousand yen. This much should have been apparent to any ceramics appraiser and the TV programme received much negative feedback over their valuation.

The much more intriguing case came in 2020 with another NHK programme featuring a mysterious yōhen. This one was supposedly stored at Fugen-in on Mt. Koya and has a matching box written by the 8th Generation Iemoto of Omotesenke. Despite consulting ceramics experts and performing tests, the TV show was undecided about the bowls legitimacy. While this bowl looked much more convincing than the 2016 bowl, most tenmoku enthusiasts dismiss it as yet another fake, or at least cast doubt on its authenticity, and especially the authenticity of its supporting documentation. The bowl itself, ‘real’ or not, is rather stunning, so it is continuously disappointing to see art that can stand on its own marred by controversy and false claims of historicity.

Outside of yōhen, there are numerous ‘fake tenmoku’ that circulate the markets. Often modern pieces that have been artificially aged with acid or abrasives, or even original excavated shard footrings that have been joined to a modern body and refired.

Reproduction

Fig. 9: Yōhen by Yoshiaki Dōbuchi

Many have tried to recreate yōhen but only recently has anyone really succeeded. A handful of potters in Japan and China, through decades of research and thousands of bowls of experimentation have been able to, sometimes, make yōhen bowls. Luck still plays a large factor. 

With the inspection of the Hangzhou shards, a 2016 x-ray analysis of the Fujita bowl, and a 2023 study of a yuteki bowl, researchers have begun to ascertain the source of yōhen’s colour and iridescence. The use of heavy metals and cobalt pigments that had long been theorised has now been ruled out, and simple thin film interference does not explain all of the observed phenomena. Research suggests that yōhen’s blue iridescence is a result of structural colour, the same phenomenon responsible for the blue of morpho butterflies’ wings. How this is formed in the kiln is another question. One of the potters who was successful in reproducing yōhen, Nagae Sōkichi IX, theorises that the effect comes from the introduction of fluorite into the kiln, perhaps suggesting that the original yōhen were not just happy accidents, but rather intentionally created, albeit with a low success rate.

Among the successful potters are Oketani Yasushi, Nagae Sokichi IX, Seto Takemi, Lu Jinxi, Ōe Takamoto, Zhāng Zhōngqīn, Hiroyuki Kuze, and Yoshiaki Dōbuchi, 4th-generation leader of Touan.

Yuteki (油滴)

Fig. 9: Yuteki, Museum of Oriental Ceramics

Leaving the glimmering world of yōhen behind, we move to the next tier in Sōami’s ranking: yuteki.

Yuteki: The second treasure. These also have dark black base glaze with light mottled patterns, and pale purple and blue stars are scattered on the outside and inside.  Worth 5,000 rolls of silk

That’s not quite as much as 10,000 bolts, but still plenty expensive. Yuteki (油滴) means oil-drops, referring to the silvery spots that dot the dark glaze. As Sōami said, these bowls are much more numerous and they also vary significantly.

Some have small silvery dots, others have blue or rust coloured dots that are dripping and elongated. One famous example is the chawan pictured below, which is held by the Kyūshu National Museum. The bowl passed through the hands of either Rikyū or Oribe and was later owned by Matsudaira Fumai. It has fine specks that appear silver at first but have a subtle colouration and gradient. The rim is covered with a gold fukurin.

Fig. 10: Yuteki, Kyūshu National Museum

Below is a modern Yuteki made by Tanaka Kōsen. Its silver fukurin stands out against the deep deep blue-black glaze. The oil spots themselves are subtle and subdued and are only revealed upon close inspection.

Fig. 11: Yuteki by Tanaka Kōsen

Compared to the original Song Dynasty yuteki kensan, this bowl has a wider shape, making it easier to use with modern matcha whisks. Some tea schools have special chasen designed for tenmoku bowls, but none are like those used in Song China or medieval Japan. If we look at the iconography, it is clear that the original chasen that were used with these bowls were long and narrow straight tines. The splaying and separating of the inner and outer tines seemingly occurred in the 1400–1500s, and the curving of the tips wasn't until the 1600s. 

Kensan (建盞) / Nogime (禾目)

 

Fig. 12: Kensan, Tokyo National Museum

After his entry on yuteki, Sōami writes:

Kensan: These are always numerous. The finest examples are comparable to yuteki. The base is black and silver.  The glaze is smooth, gentle, and has some dazzling stars. Worth three thousand pieces of silk.

Sōami uses the generic term kensan for all Jian bowls that aren’t yōhen or yuteki, which makes sense as these are the most common variety of kensan. They have streaky glazes in silver, blue, and rust red, for which they are known in English and Chinese as hare’s fur bowls. Remember those Song Dynasty writings from Part 1? These are the hare’s fur patterns they were referring to.  

Interestingly, in Japanese, the standard term today is nogime (禾目), referring to the hairs on an ear of grain. 

Usan

Fig. 13: Potential Usan, from the Sinan Shipwreck

The last style of kensan listed by Sōami is usan

Usan: Tōsan-shaped. The clay and glaze is the same as kensan. There are large and small sizes. Worth 300 rolls of silk.

This entry is a little mysterious as unlike the previous styles, this classification is not still in use today. As such, there are a few different interpretations of this definition. Usan is spelled using the kanji 烏盞 with the first kanji meaning ‘bird’ generally or ‘crow’ specifically, and it is usually taken to mean jet-black kensan. Lacking any ornament, they are much cheaper and less desirable. In fact, some copies of the text just say “Price: cheap”. 

The description 'tōsan-shaped' has been the subject of some scholarly intrigue but the common conclusion is that it refers to a completely different shape altogether, one that is flatter with an everted lip (as pictured).

Tenmoku

Tahi-san and Bessan

Fig. 14: Taihi-san Tenmoku, Tokyo National Museum

Leaving the world of kensan behind we reach the ordinary tenmoku. That’s right, for Sōami and his contemporaries, and for centuries of Japanese art evaluation and tea culture, kensan, yuteki, and yōhen were not considered tenmoku. Instead, 'tenmoku' referred to chasan, bowls of this shape, made in China in kilns other than Jian kiln.

The first two in Sōami’s list are often treated together. 

Bessan: Made of Tenmoku clay. Light brown and black glaze. Various floral and bird crests. Worth 1000 rolls of silk

and

Taihi-san: Also made of Tenmoku clay. Glazed with a light amber color. Pale purple stars scattered inside and out. Price: cheap.

Fig. 15: Taihi-san Tenmoku, Tokyo National Museum

Today, these are both called Taihi-tenmoku and are tenmoku fired in the Jizhou kilns in Jiangxi, China. They typically have very low foot rings and lack the grooved lip found on kensan, simply constricting slightly at the top, if at all. Many feature naturalistic glaze effects that resemble a tortoiseshell pattern. Others, like Sōami wrote, have bird and flower designs made by using paper stencils and straw ash. Evidently the ones with these designs fetched a higher price in Sōami’s day.

Ordinary Tenmoku

Fig. 16: Yulinting Kiln Chasan (Tenmoku)

Lastly, Sōami simply lists

Tenmoku: These are not of any use to the Imperial Court. They are used by feudal lords, outsiders, and guardhouses. Hai-katsugi is considered the top grade. Not worth pricing.

Interestingly, a later copy prices them at 500 rolls of silk..more on that in a bit.

Here, Sōami has lumped all of the other Chinese chasan under the label ‘tenmoku’ and says they’re not worthy of his attention. Of course, to him, any of the domestically produced Seto tenmoku would be beyond worthless to him. However, the one type he does name, hai-katsugi, will soon be quite valuable.

Tenmoku vs Chawan

Before we leave Sōami behind, it is worth pointing out that this text is one reason I (and others) prefer to say “tenmoku” instead of “tenmoku chawan”. 

Sōami separates the Kundaikansōchōki chapter on tea bowls into two sections: the first titled ‘earthenware’ or ‘pottery’ which contains all the classifications tenmoku and kensan outlined above, and the following section named ‘various chawan’, exclusively talks about porcelain and celadon wares. Additionally, in his decoration records, and others from this time, chawan and kensan or tenmoku are always listed separately and the term “tenmoku chawan” never appears until much much later. Scholars have agreed that at this point, the word ‘chawan’ exclusively referred to porcelain and celadon wares and that kensan and tenmoku were viewed separately.

Hai-katsugi Tenmoku

Fig. 16: "Juko Tenmoku", Hai-katsugi tenmoku

Though only briefly mentioned by Sōami in the Kundaikansōchōki, hai-katsugi tenmoku began to become immensely popular in the 1500s, eventually eclipsing all of the other styles by the end of the century as the most prized and coveted style of tenmoku.  

Hai-katsugi (灰被) literally means ‘ash-covered’, in reference to their often silvery-greyish appearance. However, this name is not to be taken literally. Hai-katsugi tenmoku, like the other tenmoku and the kensan were fired in saggars: which are individual ceramic boxes that shield the bowls during the firing process, which means that ash from the burning wood can’t settle on the bowls in the kiln. How the effect was actually achieved has long been debated, but current consensus is that it comes from double-layering the same glaze.

Compared to the metallic brilliance of kensan, hai-katsugi tenmoku have a more subdued and mysterious appearance, with occasional flashes of metallic lustre or iridescence. This is precisely why these bowls became emblematic of the budding wabicha movement in the late 1400s, with its chilled and withered aesthetic sense. Compared to the flashy display of wealth that was the tea gathering of the early to mid 1400s, this new style attempted to harmonise beautiful Chinese wares with more rustic Japanese ones, swapping bright jade-green celadon for dull-yellow, and swapping lustrous kensan for these more muted haikatsugi tenmoku. The forerunner of this aesthetic movement was Murata Jukō, who likely met Nōami and Sōami and received a copy of the Kundaikansōchōki.  While Sōami doesn’t provide any description for hai-katsugi tenmoku in his text, Jukō’s adopted son and successor, Sōju, gives us our earliest description of them in 1523:  

Haikatsugi: The upper glaze is entirely black; the clay is visibly black; where the glaze stops, the lower yellow glaze is revealed... Sometimes the yellow glaze follows the edge where the glaze stops; sometimes it extends by 2 or 3 bu. If no yellow glaze appears, then it is merely an ordinary Tenmoku…The "silver" of haikatsugi Tenmoku refers to a white, muddy appearance. Its presence or absence is of no consequence. What is important is that the underlying glaze be yellow.

Unlike kensan which were known to come from the Jian Kilns since their introduction to Japan, the origin of hai-katsugi tenmoku was only confirmed as the Chayang Kilns in the past twenty years. This is due in part to the fact that unlike the word kensan which exists as jianzhan in Chinese, hai-katsugi tenmoku is an entirely Japanese name and concept. 

Fig. 18: Hikisetsu's Hai-katsugi tenmoku, as mentioned in the Yamanoue Sōji-ki, Tokugawa Museum

As Jukō’s withered aesthetic evolved into wabicha, hai-katsugi tenmoku became increasingly popular and by the time that wabicha had reached its zenith with Sen-no-Rikyū in the late 1500s, they were the clear tenmoku of choice. Although Korean and domestic bowls were the trendy chawan, these old Chinese antiques were still valued. I mentioned earlier that the value order for tenmoku had inverted, and we know this because of a valuation by Yamanoue Sōji, one of Rikyu’s foremost disciples, who said this in 1588:

Of the three in the realm, two are in the possession of the Regent. Hikisetsu’s Tenmoku is at the Aburaya in Sakai. All are hai-katsugi. There are upper, middle, and lower grades of hai-katsugi tenmoku, though I do not know their number. Three of the top-grade have from ancient times been rested upon famous stands and are meibutsu Tenmoku existing in various places.

Kensan: among these are Yōhen, Yuteki, Usan, Bessan, and Taihisan. I, Sōji, have seen all such Tenmoku. They are low in value.

The change in valuation can also be seen in the Seto tenmoku of the time. Compared ti the earlier Seto tenmoku which sought to replicate Jian bowls/kensan, Seto tenmoku of the 1500s adopted the angular foot trimming, subtler lip flair, and mottled glaze that are characteristic of hai-katsugi tenmoku.

Fig. 19: Muromachi-era Seto Tenmoku, hai-katsugi style

In less than 100 years after Sōami’s writing, the classical order has been flipped. This is quite representative for this tumultuous time in Japanese history, a period where the social hierarchy had been repeatedly upended and countless rebellions rose and fell. As things calmed down in the following Edo Era and society's social hierarchy was solidifying, the old order of tenmoku value was restored. Make of that what you will. 

 

Part 3 will explore Tenmoku-dai and the actual usage of tenmoku in a tea setting and its evolution over time. 

Footnotes

¹While there are dozens of copies, they vary in content and colophon and none are thought to be the original. The oldest ‘trustworthy’ manuscript is from 1511, and the oldest copy is from 1476. To make matters more confusing, there are many copies/versions of this text with different names and slightly different content.

²This loose collection of treasures consisting primarily of paintings and ceramics, is commonly known today as the Higashiyama Gomotsu (東山御物 - Higashiyama Treasures), so called because during his final years in the 1480s, Ashikaga Yoshimasa had retired to his Higashiyama estate and practiced tea and incense. Despite the name, most of these treasures were not acquired by Yoshimasa, but by his predecessors. During the violence of the Ōnin Wars in the mid-1400s, many of these treasures were lost or destroyed. Following this, the weakened financial state of the Ashikaga Shogunate necessitated the sale of many of these items. As Yoshimasa became to be revered as one of the founders of chanoyu in the subsequent century, items formerly from his personal collection attained a legendary status.

³These classifications predate this text with the oldest attested usage being in Nōami’s 能阿相伝集. As this is also Nōami’s text, the descriptions are similar. I decided to use the Kundaikansōchōki as it is much more accessible and relevant due to its distribution

⁴Like almost everything surrounding Japanese tea culture, the kanji spelling of this word has changed over the centuries.

⁵ This is the historical leader that Toranaga in the book and TV show Shogun is based on

⁶ the older spelling used in the time of the Kundaikansōchōki was 伏輪 with a similar meaning