The Monorecchio is a single aluminum disc, approximately 170mm across, milled to an optical finish that shifts in changing light. It was made in 1965 by Getulio Alviani, an Italian artist and leading figure in arte programmata — the kinetic art movement that put work in MoMA that same year. At the disc's center is a cutout in the exact shape of an ear, which is how it's worn: sliding flush against the side of the head.

The name means "single ear," which tells you what Alviani was actually after. Not jewelry — a device for isolating a body part and presenting it as geometry. The auricle becomes the subject of the disc rather than its wearer — arguing that even our ear can be the center of attention. And we're listening.