Do you want to buy one-sided convex or double-sided convex in Go?

Weiqi is used to being one-sided in the middle.

From ancient times to the present, Go is made of stone, ceramics and wood. From the Nanzhao period, which began in the Tang Dynasty, there was a kiln-changed Weiqi made of mineral powder (Fu, written in the middle and late Tang Dynasty in 958, recorded that "the wooden platform was set up and the son came out of the furnace in southern Yunnan"), and there were also glass ones.

Chessboard features:

There are 19 vertical and horizontal parallel lines intersecting at equal distance on the disk surface, and * * constitutes19 ×1intersection points (hereinafter referred to as "points"). The overall shape of the chessboard and the transverse direction of each grid are slightly shorter, generally 2.4 cm ×2.3 cm per grid. There are nine points on the disk, called the star position, and the central star position is also called "Tianyuan".

When playing chess, you should put the dice on the stars (except the first one). Chessboards can be divided into corners, sides and midriffs. In the initial study, there were 13× 13 and 9×9 chessboards. In addition, some modern unearthed cultural relics are rare chessboards of 15× 15 and 17× 17.