White Copper Constellations Blank Plaque

The old astronomers grouped the stars near the ecliptic and the equator into twenty-eight mansions, seven for each direction. The Azure Dragon of the east is Horn, Neck, Root, Room, Heart, Tail, Winnowing Basket; the Dark Warrior of the north is Dipper, Ox, Girl, Emptiness, Rooftop, Encampment, Wall; the White Tiger of the west is Legs, Bond, Stomach, Hairy Head, Net, Turtle Beak, Three Stars; the Vermilion Bird of the south is Well, Ghost, Willow, Star, Extended Net, Wings, Chariot. The names are obscure and few can recite them in order — buyers often ask me to run through the list. The system was used to count days and fix the solar terms, and both farming and sacrifice were scheduled by it.

The plaque is a vertical rectangle with the mansions laid across the front: each star a small dot, stars of the same mansion joined by fine lines, twenty-eight groups filling one face. The lines are fine and the dots small, so dense that the individual marks nearly vanish; you have to lean in to tell which stars they are. The back is plain, without a single character. The face has no border — the mansions run close to the edge, with only a narrow ridge to contain them.

Cutting pattern this dense, the difficulty is continuity of line. A line that breaks halfway leaves that mansion formless, and it cannot be repaired; the whole plaque is scrap. The dots are positioned first and drilled after, and a hair off sends the connecting lines crooked, which is why the layout is worked out on paper before the tool goes in. The drill bits are small, and too high a speed burns the copper, and burnt copper leaves the dot dark. The lines are harder than the dots: each must be cut in one pass, since stopping leaves a joint.

Silver and gold versions. The silver ground is cool and the star dots are left bright, so the dense pattern looks like frost at night; gold is warm, the contrast between dots and ground is smaller, the pattern blurrier, and it wants side light. Both come with a fine chain and sit at about the same height. The gold is not thick, and worn spots show the white beneath, so the difference tells. Both come from one mold; the only difference is the surface treatment.

Dust settles in the dense pattern, especially in the small pits of the stars. Clean with a soft brush, sweeping in one direction, and don't pick with a needle, which scratches the dots. When the copper dulls, press it with a dry cloth rather than wiping the whole face with a silver cloth — polished bright, the mansions lose their depth. The plaque is thin and bends under pressure, so don't sit with it in a trouser pocket; once bent, it won't go back.