This jade ring was made sometime towards the end of the Neolithic period or the beginning of the Shang dynasty, around 2000-1500 BC. Its function is unknown but such rings have been found in tombs of the Shang dynasty (1500-1050 BC) although by then they might already have been antiques.
Jade has always been pivotal in Chinese culture and much prized as a very precious material. Many Chinese through the ages have been collectors of Chinese antiques and this jade would have been revered as a precious antiquity from an early time.
Eventually it became part of the imperial art collection and in due course came to the notice of the Qianlong emperor (1736-95) who was a very enthusiastic patron of the arts. He was well known for writing comments on his objets d'art, particularly his paintings and his jades. This jade has one of his inscriptions inscribed on it. In it he says that the ring was a cup stand and that he had looked for the jade cup which he thought it originally housed. He could not find one so substituted it for a ceramic Ding ware bowl. A Ding ware bowl with an identical inscription has recently been found in the imperial palace collection.