Piaget's identity is inseparable from the idea of treating a watch as jewellery. During the second half of the twentieth century, the manufacture became particularly adept at combining ultra-thin movements, precious-metal bracelet construction, ornamental stone dials and gem setting into watches where the boundary between horology and jewellery almost disappears. The rectangular Protocole provided an ideal canvas for this approach, its disciplined geometry allowing Piaget to experiment with colour, texture and increasingly elaborate precious-metal executions.

This 1990s example is particularly striking, combining an 18K white gold case and ibracelet with a sodalite stone dial and extensive diamond setting. Rather than conventional hour markers, diamonds form bold geometric indexes around the dial, complemented by a double row of brilliant-cut diamonds surrounding the bezel. The integrated white gold bracelet is equally distinctive, alternating polished outer elements with finely ribbed central links to continue the architectural character of the case. The result is quintessential Piaget.