How to choose Go bowls

The Kurokaki Go bowl is a high-quality artwork with a beautiful appearance characterized by a clear contrast of black and white colors. The black persimmon tree needs to be dried out in the open air for many years to be used as material for wooden artifacts. It is an extremely difficult material to handle since the white and black areas have different shrinkage ratios, which may often result in cracking during the drying process.
Go bowls are finished after a number of repeated grinding and drying processes. As it is carefully dried and painstakingly crafted, the Go bowl is not easily deformed and can retain its beauty for many years.
The greatest feature of the Kurokaki (black persimmon) Go bowl is the unique appearance of the black patterns on the wood surface. Some Go bowls have a black pattern as if it is drawn with a fine brush, while others have a bold black pattern, which is a miracle of nature and you can never find two of the same design. Kurokaki (black persimmon) is rarely available on the wood market and it is difficult to tell whether it has a black pattern until it is cut. Even if the wood has black patterns after cutting, nobody knows how the black pattern will appear on the surface until the Go bowl is completely finished.
Only artisans who have been engaged in making Go bowls for many years and know the nature of this wood are able to make a black persimmon Go bowl, which makes it truly a gem and worth calling a "precious wood".

Go bowls made of Yakusugi (cedar) (over 1,000-year-old cedar trees grown on Yakushima Island, Japan), are so beautiful and graceful with their intricate and elaborate grain patterns that there are serious "Yakusugi collectors" all over the world.
Since Yakushima Island has been registered as a UNESCO World Natural Heritage Site, logging has been prohibited and the quantity of Yakusugi trees on the market is quite limited, making them extremely difficult to obtain.
The color of Yakusugi (cedar) wood is reddish-brown. It is a very beautiful wood with its unique aroma and intricate grain patterns including moku (figure) and kobu (burl).
Please note that the tree oil or fat may start to seep as time goes by as the wood contains a lot of oil and fat.

Generally, Go bowls made of kuwa (mulberry) are regarded as the highest quality. Among them, the name "shimaguwa" is only used for Go bowls made from the mulberry trees grown on Mikura-jima Island.
Shimaguwa (island mulberry) grows on Mikura-jima Island under a specific environment influenced by the volcanic geology, unique climate, and ocean currents. The island mulberry is quite different from the mainland-grown mulberry in terms of the density of annual rings and elaborateness. Island mulberry is exceptional, with a light moss green that can be seen during the cutting and grinding process amid ochre colors, and the color change to a deep golden as time goes by. Unlike the mainland, the growing environment of Mikura-jima Island makes logging and transportation very difficult, which is another reason for the rarity and popularity of island mulberry. In general, it is rare and more expensive than the Honkuwa (mulberry) Go bowl.

This wood is highly praised by Ohno Showasai, a living national treasure of Japan, who wrote in his book "Wood Craftsmanship" that "honkuwa is the best wood in the world, and no other wood is better than this in terms of grain pattern, figure, and the elegance of the color".
Except for the very expensive one-of-a-kind Go bowl, honkuwa Go bowls made of mulberry are regarded as the finest quality. Generally, honkuwa is synonymous with a high-class product.
Honkuwa is the generic term for several types of mulberry, such as Yamaguwa, Honguwa, and Jiguwa. Honkuwa has all the excellent features required to be selected as a material for Go bowls, such as the highest wood quality, clear annual rings, a golden color that becomes more beautiful over time, showing different expressions depending on the viewing angle and strong enough to be used as a walking stick.

The Honkaya Go bowl is made of Japanese Torreya, which is regarded as the finest Go/Shogi board material.
Honkaya is a very beautiful wood with its gentle color and close grain patterns, that are specific to Japanese Torreya. Since the wood colors are very similar to each other, honkaya Go bowls match perfectly with Go/Shogi boards made of honkaya and Hyuga kaya (grown in Miyazaki Prefecture, Japan).

Kokutan (Ebony) is a very popular wood that is considered one of the three most famous woods.
Kokutan (Ebony) wood is quite dense and hard wood with high level of durability as it grows very slowly.

Some ebony wood piece is heavy and dense enough to sink in the water.
By taking advantage of these characteristics, ebony is often used to make piano keys, Buddhist family alter and its fittings.
Dark black and pale red colored stripes are unique design, that attract more serious collectors.
It is quite rare wood as it is not only hard to purchase but also to process.

Most of the Go bowls made from mulberry, zelkova, pasania, camphor, oak, etc. use masame (straight grain) wood. When you view a Go bowl from above, the lid has straight vertical (horizontal) patterns. When viewed from the side, the grain runs vertically.

Moku refers to the intricate grain patterns and figures that rarely appear on the area of branching or close to the tree root in the forms of localized twists and curvatures. These are caused by the specific conditions and unique environment where the tree grows.
The wood with the moku figure is a high-end material because of its rarity, aesthetic value, and excellent decorative value.
There are various types of moku figures depending on the shapes and characteristics, such as kujaku moku (peacock figure), budo moku (grape figure), tama moku (ball figure), tora moku (tiger figure), uzura moku (quail figure), awa moku (bubble figure), chijimi moku (shrinking figure), chogan moku (bird's-eye figure), botan moku (peony figure), and torafu (tiger stripe).

Kobu is a group of burls formed on the surface of wood. Since these burls appear infrequently and in small quantity, the wood with burl is regarded as a truly rare material. The beauty of the burl makes the wood highly valued as a material for artwork with decorative purposes.