White Copper Taiji Peace Plaque

The two characters taiji come from the Yizhuan: in change there is taiji, which gives rise to the two modes, which give rise to the four images, which give rise to the eight trigrams. It does not describe a diagram but the breath before heaven and earth divided. Later people drew it as two fish, black and white, circling each other, and the picture travelled further than the text; far more people recognize the diagram today than have read the Yizhuan. The yin-yang fish form now in general use is thought to have settled only after the Song, and earlier diagrams were drawn otherwise. In the diagram one fish faces the other's tail and one the other's head, so the turning has no starting point, and that is what separates it from other auspicious images.

The peace plaque is an old form in jade carving: a plain face with nothing cut on it, taking the phrase safe and without incident, and called in the trade the no-incident plaque. A plain face is the hardest test of the stone, since there is nothing to hide behind. Copper does not fear that; it fears emptiness, so most copper plaques raise a little pattern on the face, and the taiji diagram is the commonest choice, turning inside a circle without shouting.

Cast in white copper as a round plaque, taiji on the face, flat on the back. In the two fish, yin holds a yang eye and yang a yin eye, and at small scale that detail is the first thing lost, reduced to two solid blocks of colour until the sense of turning goes. When choosing, check whether the two dots are still there and whether they sit true. The rim should be rounded, which rests against the body without digging in and protects the pattern from knocks.

Two versions, the pendant alone or with a leather cord. The leather is deep in colour, suits the old tone of the copper, does not cling cold and sweaty in summer, and can be adjusted in length: wherever the knot is tied, that is where the pendant sits. The pendant alone is for anyone who already owns a chain. The leather comes in dark brown and black, and with use it will fur up and go patchy, which is normal and no reason to oil it.

The peace plaque is the easiest thing to give, since there is no recipient to pick and no meaning to explain. Elders, a young person just starting work, a friend about to travel far: all fine. The words are one line, a wish for peace, no exaggeration and no burden on anyone. The hole is at the top, so cord or chain both work, and a dark cord sets it off better. The price is modest, so the gift is not rude and does not put the recipient under pressure to reciprocate, and most people put it on straight away.