The Rolex Day-Date 18038 with an Onyx dial is a highly sought-after 36mm luxury watch (circa 1977–1988) featuring a deep black, polished stone dial, typically with no hour markers for a minimalist, stark aesthetic. It houses the Caliber 3055 movement—the first to offer a "single-quickset" date function—housed in 18k yellow gold with a sapphire crystal.