Lisbon, Portugal—Americo Amorim, known as the “King of Cork” for building his fortune on cork stoppers and believed to be Portugal’s wealthiest man, died Thursday. He was 82.

According to a report by Barry Hatton in the Associated Press, Amorim’s fortune was recently estimated by Forbes at $5 billion. His company, Corticeira Amorim, is the world leader in cork production. Portugal is the world’s largest cork producer, accounting for about half of global output.

With plastic stoppers for wine bottles encroaching on his market, Amorim diversified cork uses into areas such as insulation and furniture. He created a conglomerate, Grupo Amorim, which expanded his business into wine production and tourism. Amorim also held significant stakes in Portuguese financial, telecom and energy companies.

Amorim was the fifth of eight children born to a modest family in the town of Mozelos, in northern Portugal, in 1934. At 18, he started work at the small cork company founded by his grandfather in 1870. He inherited a 2.5% share in the family cork company and from that he built his business empire on the back of an export drive. He is survived by his wife, three daughters and grandchildren.

Reuters reported Amorim's nephew Antonio Rios de Amorim took over as chief executive at Corticeira in 2001. Amorim's daughter Paula Amorim is overseeing the other business interests that include an oil company.