Editing Go (game) (section)

== Equipment ==
{{Main|Go equipment}}
[[File:Four Arts China Japan.jpg|thumb|right|Go portrayed as part of East-Asian culture. (The goblet in the middle is from the Nihon Ki-in.)]]

It is possible to play Go with a simple paper board and coins, plastic tokens, or white beans and coffee beans for the stones; or even by drawing the stones on the board and erasing them when captured. More popular midrange equipment includes cardstock, a [[laminate]]d [[particle board]], or wood boards with stones of plastic or glass. More expensive traditional materials are still used by many players. The most expensive Go sets have black stones carved from slate and white stones carved from translucent white shells (traditionally ''[[Meretrix lamarckii]]''), played on boards carved in a single piece from the trunk of a tree.

=== Traditional equipment ===
[[File:Go-tisch.png|thumb|upright|left|A traditional Japanese set, with a solid wooden floor board ({{nihongo2|碁盤}} ''goban''), 2 bowls ({{nihongo2|碁笥}} ''goke'') and 361 stones ({{nihongo2|碁石}} ''goishi'')]]

==== Boards ====
The [[Go board]] (generally referred to by its Japanese name ''goban'' {{nihongo2|碁盤}}) typically measures between {{convert|45|and|48|cm|abbr=on}} in length (from one player's side to the other) and {{convert|42|to|44|cm|1|frac=4|abbr=on}} in width. Chinese boards are slightly larger, as a traditional Chinese Go stone is slightly larger to match. The board is not square; there is a 15:14 ratio in length to width, because with a perfectly square board, from the player's viewing angle the perspective creates a foreshortening of the board. The added length compensates for this.{{sfn|Fairbairn|1992|pp=142–143}} There are two main types of boards: a table board similar in most respects to other gameboards like that used for chess, and a floor board, which is its own free-standing table and at which the players sit.

The traditional Japanese ''goban'' is between {{convert|10|and|18|cm|abbr=on}} thick and has legs; it sits on the floor (see picture).{{sfn|Fairbairn|1992|pp=142–143}} It is preferably made from the rare golden-tinged [[Torreya nucifera|Kaya]] tree (''Torreya nucifera''), with the very best made from Kaya trees up to 700&nbsp;years old. More recently, the related [[Torreya californica|California Torreya]] (''Torreya californica'') has been prized for its light color and pale rings as well as its reduced expense and more readily available stock. The natural resources of Japan have been unable to keep up with the enormous demand for the slow-growing Kaya trees; both ''T. nucifera'' and ''T. californica'' take many hundreds of years to grow to the necessary size, and they are now extremely rare, raising the price of such equipment tremendously.{{sfn|Fairbairn|1992|pp=143–149}} As Kaya trees are a protected species in Japan, they cannot be harvested until they have died. Thus, an old-growth, floor-standing Kaya ''goban'' can easily cost in excess of [[USD|$]]10,000 with the highest-quality examples costing more than $60,000.<ref>{{citation | url=http://www.kiseido.com/go_equipment.htm | title = Kiseido clearance sale}} lists the regular price for a Shihomasa Kaya Go Board with legs ({{convert|20.4|cm|abbr=on|disp=or}} thick) as $60,000+</ref>

Other, less expensive woods often used to make quality table boards in both Chinese and Japanese dimensions include [[Thujopsis|Hiba]] (''Thujopsis dolabrata''), [[Katsura tree|Katsura]] (''Cercidiphyllum japonicum''), [[Agathis|Kauri]] (''Agathis''), and Shin Kaya (various varieties of [[spruce]], commonly from Alaska, Siberia and China's [[Yunnan Province]]).{{sfn|Fairbairn|1992|pp=143–149}} So-called ''Shin Kaya'' is a potentially confusing merchant's term: ''shin'' means 'new', and thus ''shin kaya'' is best translated 'faux kaya', because the woods so described are biologically unrelated to Kaya.{{sfn|Fairbairn|1992|pp=143–149}}

==== Stones ====
A full set of Go stones (''goishi'') usually contains 181 black stones and 180 white ones; a 19×19 grid has 361 points, so there are enough stones to cover the board, and Black gets the extra odd stone because that player goes first. However it may happen, especially in beginners' games, that many back-and-forth captures empty the bowls before the end of the game: in that case an exchange of prisoners allows the game to continue.

Traditional Japanese stones are double-convex, and made of [[clam]]shell (white) and [[slate]] (black).{{sfn|Fairbairn|1992|pp=150–153}} The classic slate is nachiguro stone mined in [[Wakayama Prefecture]] and the clamshell from the Hamaguri clam (''[[Meretrix lusoria]]'') or the [[Korean hard clam]]; however, due to a scarcity in the Japanese supply of these clams, the stones are most often made of shells harvested from [[Mexico]].{{sfn|Fairbairn|1992|pp=150–153}} Historically, the most prized stones were made of [[jade]], often given to the reigning emperor as a gift.{{sfn|Fairbairn|1992|pp=150–153}}

In China, the game is traditionally played with single-convex stones{{sfn|Fairbairn|1992|pp=150–153}} made of a composite called [[Yunzi]]. The material comes from Yunnan Province and is made by [[sintering]] a proprietary and trade-secret mixture of mineral compounds derived from the local stone. This process dates to the Tang dynasty and, after the knowledge was lost in the 1920s during the [[Chinese Civil War]], was rediscovered in the 1960s by the now state-run Yunzi company. The material is praised for its colors, its pleasing sound as compared to glass or to synthetics such as [[melamine]], and its lower cost as opposed to other materials such as slate/shell. The term ''yunzi'' can also refer to a single-convex stone made of any material; however, most English-language Go suppliers specify Yunzi as a material and single-convex as a shape to avoid confusion, as stones made of Yunzi are also available in double-convex while synthetic stones can be either shape.

Traditional stones are made so that black stones are slightly larger in diameter than white; this is to compensate for the optical illusion created by contrasting colors that would make equal-sized white stones appear larger on the board than black stones.{{sfn|Fairbairn|1992|pp=150–153}}{{efn|1=See [[Overshoot (typography)|Overshoot]] in Western typography for similar subtle adjustment to create a uniform appearance.}}

[[File:Bowls dwindsor.jpg|thumb|left|An example of single-convex stones and ''Go Seigen'' bowls. These particular stones are made of [[Yunzi]] material, and the bowls of jujube wood.]]

==== Bowls ====
The bowls for the stones are shaped like a flattened sphere with a level underside.{{sfn|Fairbairn|1992|pp=153–155}} The lid is loose fitting and upturned before play to receive stones captured during the game. Chinese bowls are slightly larger, and a little more rounded, a style known generally as ''Go Seigen''; Japanese ''Kitani'' bowls tend to have a shape closer to that of the bowl of a [[snifter]] glass, such as for [[brandy]]. The bowls are usually made of turned wood. [[Mulberry]] is the traditional material for Japanese bowls, but is very expensive; wood from the Chinese [[jujube]] date tree, which has a lighter color (it is often stained) and slightly more visible grain pattern, is a common substitute for rosewood, and traditional for Go Seigen-style bowls. Other traditional materials used for making Chinese bowls include [[lacquer]]ed wood, [[ceramic]]s, stone and woven straw or [[rattan]]. The names of the bowl shapes, ''Go Seigen'' and ''Kitani'', were introduced in the last quarter of the 20th century by the professional player [[Janice Kim]] as homage to two 20th-century professional Go players by the same names, of Chinese and Japanese nationality, respectively, who are referred to as the "Fathers of modern Go".<ref name=jowa.html>{{cite web|first=John|last=Fairbairn|title=MindZine – Go – Feature: Honinbo Jowa|publisher=Mind Sports WorldWide|url= http://www.msoworld.com/mindzine/news/orient/go/history/jowa.html|access-date=15 May 2014|archive-url= https://web.archive.org/web/20110608002240/http://www.msoworld.com/mindzine/news/orient/go/history/jowa.html|archive-date=8 June 2011}}</ref>

=== Playing technique and etiquette ===
[[File:Playing weiqi in Shanghai.jpg|thumb|Go players demonstrating the traditional technique of holding a stone]]

The traditional way to place a Go stone is to first take one from the bowl, gripping it between the index and middle fingers, with the middle finger on top, and then placing it directly on the desired intersection.<ref name="style">{{Citation|publisher=[[Nihon Ki-in]] |url=http://www.nihonkiin.or.jp/lesson/knowledge-e/uchikata-e.htm |title=A stylish way to play your stones |access-date=2007-02-24 |url-status=dead |archive-url=https://web.archive.org/web/20070513214109/http://www.nihonkiin.or.jp/lesson/knowledge-e/uchikata-e.htm |archive-date=2007-05-13}}</ref> One can also place a stone on the board and then slide it into position under appropriate circumstances (where it does not move any other stones). It is considered respectful towards White for Black to place the first stone of the game in the upper right-hand corner.<ref>{{cite web|url=http://senseis.xmp.net/?PlayingTheFirstMoveInTheUpperRightCorner |title=Sensei's Library: Playing the first move in the upper right corner |publisher=Senseis.xmp.net |date=2011-09-19 |access-date=2014-03-25}}</ref> (Because of symmetry, this has no effect on the game's outcome.)

It is considered poor manners to run one's fingers through one's bowl of unplayed stones, as the sound, however soothing to the player doing this, can be disturbing to one's opponent. Similarly, clacking a stone against another stone, the board, or the table or floor is also discouraged. However, it is permissible to emphasize select moves by striking the board more firmly than normal, thus producing a sharp clack. Additionally, hovering one's arm over the board (usually when deciding where to play) is also considered rude as it obstructs the opponent's view of the board.

Manners and etiquette are extensively discussed in 'The Classic of WeiQi in Thirteen Chapters', a [[Song dynasty]] manual to the game. Apart from the points above it also points to the need to remain calm and honorable, in maintaining posture, and knowing the key specialised terms, such as titles of common formations. Generally speaking, much attention is paid to the etiquette of playing, as much as to winning or actual game technique.