Now, recent archeological work at the famous tomb of Liu He—better known as the Marquis of Haihun—has yielded what researchers believe are the oldest known steel acupuncture needles. Instead, a tiny jade tube stored inside a gilded lacquered box placed near Liu He’s remains contain a set of corroded and fragmented steel needles. Chinese artisans in earlier eras crafted acupuncture needles from a variety of metals, each with their own drawbacks. This allowed crafters to create items like the Marquis of Haihun’s steel needles, whose 0.3–0.5 millimeter diameters are comparable to today’s acupuncture needles. Gu Man, director of the China Academy of Chinese Medical Sciences, explained that the existence of these needles represent the oldest physical evidence of steel medical needles in ancient China.