When Raymond King helped his mother clear out old belongings in her New York apartment, little did they know an unassuming bronze vessel, nestled among other antiques, was a lost treasure crafted at least 2,800 years ago in China.

King discovered its origin last year when he invited a researcher from Sotheby's auction house to look at his mother's collection. The next day he was told the bronze was stolen from China in 1984.

"My grandfather got it from a dealer … and then gave it to my mother," the Portland, Oregon-based entrepreneur told China Daily. "We had no idea (when and for how much it was bought), but once we understood it was stolen, my mom's reaction was just, 'Give it back.'"

The bronze ritual vessel, named "Feng Xingshu Gui", was crafted sometime between 877-771 BC in the Western Zhou Dynasty. Measuring 18 centimeters high (7 inches) and 21 centimeters (8.3 inches) in diameter, and weighing about 6 kilograms (13.2 pounds), it is composed of a large bowl adorned by double handles in the design of a coiled-nose animal face, resting on three animal-shaped feet.