Hong Kong's fifth richest man spent nearly £50m on diamonds, which he named after his daughter Josephine A flamboyant Hong Kong billionaire who bought the world's most expensive diamondis expected to buy a skyscraper in the City of London. A company controlled by Joseph Lau, Hong Kong's fifth richest man, is set to buy 88 Wood Street, according to the Evening Standard. Chinese Estates is buying the tower, designed by Richard Rogers, for £270m. His company also owns Goldman Sachs' London headquarters, and he previously owned a house in Belgravia with a gold-lined swimming pool. In November, Mr Lau, who is worth £8bn, spent almost £50m on two diamonds in less than 24 hours, and named both after his daughter.