The circular disc with a large central opening. The stone of a translucent green tone with brown inclusion.

Tom Man-loong went by his preferred name of K. S. Tom, and was the founder of Tom Construction Co., one of the leading construction firms in Hong Kong after WWII. He specialized in high-end residences on the Peak, and was responsible for constructing the Hong Kong Jockey Club's clubhouse in the New Territories as well as service reservoirs for the Botanical Garden at Tai Wan on Lamma Island.

K. S. Tom always had a keen interest in Chinese archaeology and cultural artifacts. He amassed a large amount of Chinese archaic jade carvings, many of which were showcased at the City Museum & Art Gallery at the Hong Kong City Hall, the precursor to the Hong Kong Museum of Art.

In 1970, K. S. Tom became an early member of Hong Kong's prestigious Min Chiu Society, a group of collectors who met every month to discuss Chinese antiquities and planned public exhibitions.

He left dozens of letters left to his family including important correspondences with curators in Hong Kong and the U.K. Some examples include:

A July 19th 1969 letter by J. C. Y. Watt stating Mr. Tom has been named an honorary adviser to the Select Committee of the Urban Council at the City Museum & Art Gallery at the Hong Kong City Hall.

A March 24th 1970 introduction letter by S. G. Davis, Chairman of the Archeological Society at the Hong Kong University, recommending Mr. Tom to visit colleagues and collections at various museums around the world.

An April 28th 1970 introduction letter by John Warner, curator of the City Museum and Art Gallery at the Hong Kong City Hall, to Mr. John Ayers, so that Mr. Tom can visit the collection at the Victoria and Albert Museum in London.

A May 15th 1970 certification by Philp Wen-Chee Mae, President of the Min Chiu Society of Hong Kong, about Mr. Tom's acceptance into the association.