Japanese Blue and Green ＃13 Kofun Murals

Japanese Blue and Green #13

In the previous two posts, we explored how blue and green were perceived in the Asuka period. This time, we'll examine the 'Ao' in kofun murals as examples where we can actually verify the colors. While the scarcity of written records makes it difficult to analyze color perception, nothing can replace the experience of seeing the actual artifacts that remain—they truly make the heart leap with excitement.

◆Ōzuka Kofun

The Ōzuka Kofun in Fukuoka Prefecture is considered the pinnacle of decorated tombs. Built around the mid-6th century, its chamber murals use six colors—red, yellow, green, black, white, and gray—the most colors found in any Japanese kofun mural, and their quality is simply overwhelming. While the identity of those buried remains unknown, the chamber structure suggests four people were interred there.

(Image: Ozuka Ancient Burial Mound Museum)

The image above is a photograph of a replica of the murals. The actual stone chamber is sealed within a preservation facility and is only open to the public twice a year for viewing through glass. The replica can be viewed anytime at the Ozuka Ancient Burial Mound Museum, a facility adjacent to the kofun, where visitors can experience a nearly life-sized stone chamber.

By the mid-6th century, envoys from Baekje would have been frequently visiting Japan. Northern Kyushu in particular served as the gateway for trade with the continent, yet the Ōzuka Kofun murals show no apparent influence from Five Elements philosophy.

The subjects depicted include horses, quivers, shields, swords, bows, and several types of geometric patterns. The horses are carefully rendered down to their tack. However, because these murals bear considerable resemblance to those found in Goguryeo-period sites, there is strong support for the theory that they were created by continental immigrants. Perhaps the work was carried out under direct instruction from them.

The greenish pigment is known as green earth, composed of glauconite or celadonite, and is a green pigment whose color derives primarily from iron.

Glauconite	Celadonite (Image: Oimachi website)

As mentioned at the beginning, the colors used in the murals are listed as "red, yellow, green, black, white, and gray." Red is from iron oxide (bengala), yellow from yellow ochre, black from manganese earth, and white from white clay. While it's unclear which parts were considered "blue," what was initially identified as "blue" at the time of discovery has recently been determined to be "discolored gray," hence the designation "gray." This gray pigment is a mica clay mineral similar to green earth—despite their different colors, they share similar compositions.

From the replica images, it's difficult to see two distinct types of blue-based colors, but in any case, both the gray pigment and green earth would have been considered 'Ao' at that time.

Even so, it's truly amazing that they accomplished such work in the darkness, relying only on torchlight.

◆Takamatsuzuka Kofun

The Takamatsuzuka Kofun, discovered in 1972, was built during the Fujiwara-kyō period (from 694) and features subjects based on Yin-Yang and Five Elements philosophy painted on its east, west, south, and north walls. The leading theories identify the deceased as either Prince Osakabe or Prince Takechi, both sons of Emperor Tenmu.

I've compiled the historical background on a separate page. It includes information about when these kofun were built, so please be sure to check it out.

青龍(Seiryu: Blue Dragon)

The Takamatsuzuka Kofun's stone chamber contains murals following Five Elements philosophy. The four guardian deities are depicted according to their designated directions: Blue Dragon on the east, Vermillion Bird on the south, White Tiger on the west, and Black Tortoise on the north. Naturally, our focus this time is on the "Blue Dragon" on the eastern wall.

At the time of discovery	Photo taken in 2017

(Image: Asahi Shimbun Digital)

Since this is the "青龍(Blue Dragon)," this color can be said to represent the very essence of '青(Ao)' in Five Elements philosophy. In other photographic images as well, I found it generally appears close to green. The pigment is said to be a mixture of azurite and malachite, and while there appear to be areas where the blue component is locally stronger, from a modern perspective it seems fair to call it green.

Group of Female Figures on the West Wall

Let me also introduce this famous one.


(Image: Asahi Shimbun Digital)

The hakama of the figure in red is painted with azurite, while the green garment of the figure to the right uses malachite. Unlike the Blue Dragon, it seems these two colors weren't mixed here. Both are secondary copper minerals, but malachite is far more abundant in nature, with azurite apparently being worth ten times as much as malachite.

White earth is also used in this painting. Since we don't see colors like purple, yellow-green, or light blue, I believe the five colors (red, blue, yellow, black, and white) were intentionally used in accordance with Five Elements philosophy. This would mean that azurite, green, and the Blue Dragon's color were all considered '青(Ao),' suggesting there was indeed a broad range in the perception of what constituted '青(Ao).'

This means that the situation during the Fujiwara-kyō period was as shown in the diagram below. (Click here for details)

Also, I wonder if azurite blue might not have been considered '青(qing)' in China. While Japan adopted many aspects of continental culture, the color usage in the Takamatsuzuka Kofun murals might be considered uniquely Japanese.

- About lead components -

Lead components have been detected throughout the Takamatsuzuka Kofun murals. When it comes to lead, we typically think of red lead oxide or white lead pigment, but small amounts of lead have been detected even in areas with no painting. The reason remains unclear.

Though from a completely different time and place, various lead compounds have been detected in the underpainting of the Mona Lisa, leading researchers to conclude that Leonardo da Vinci used lead oxide. Lead oxide particles were also reportedly found in the underpainting of The Last Supper.

As mentioned in a previous article, lead oxide is sometimes used as a drying agent in East Asian art. While da Vinci likely used it as a drying accelerator, it may also have been a technique for achieving natural skin tones.

The Last Supper


Were they also applying something like lead oxide as an undercoating in the Group of Female Figures on the West Wall? Perhaps the desired effect wasn't just about drying. Though separated by 800 years, this major commonality of "lead components in mural underpainting" certainly fires the imagination.

Summary: The '青(Ao)' of the Five Colors and the '青(Ao)' Caps in the Twelve-Level Cap Rank System

In these two kofun murals, we've examined both 'Ao' uninfluenced by Five Elements philosophy and '青(Ao)' that shows its influence. Despite both being murals, their atmospheres were completely different. It was a momentous 150 years. We can see that the Asuka period was a historical turning point in color perception.

The influence of Five Elements philosophy has persisted in Japan ever since. We can still find numerous examples today. We can see remnants of the five colors everywhere: in the "five-colored paper strips" of Tanabata, the streamers and blue carp of koinobori, and the sumo ring (earth = yellow) with its colored tassels at the four corners.

真榊(masakaki)	五色幕(goshikimaku)

Regarding these five colors, we often see expressions like "green frequently substitutes for blue, and purple for black." Indeed, purple and green are used in 真榊(masakaki: sacred ceremonial stands) and 五色幕(goshikimaku: five-colored curtains).

While "purple for black" can be attributed to aesthetic considerations or the belief that "purple is nobler than black in Buddhism," I believe the conventional interpretation of green as a "substitute" for blue is mistaken.

Some explanations suggest it's a "substitution due to pigment availability"—perhaps influenced by the fact that "azurite was worth ten times as much as malachite"? However, '青(Ao)' in Five Elements philosophy corresponds to "wood/spring," and its essential hue is green, so the term "substitution" is inappropriate when discussing green in the five colors. The historically correct understanding should be that "the actual hue of '青(Ao)' in the five colors centers on green," and as we can see from the Blue Dragon, green is part of '青(Ao).'

Also, as mentioned in the previous article, there was no single dye for green—dyeing green always required mixing blue and yellow. This means there could actually be situations where they'd want to change green to blue for dyeing convenience. Therefore, while it's reasonable to make the blue caps of the Twelve Level Cap Rank System blue based on this dyeing consideration, otherwise, since they were influenced by Five Elements philosophy, shouldn't they indeed be depicted in green?