South Africa’s richest man, Johann Rupert, has seen his net worth surge to $17.4 billion, up $1.3 billion from $16.1 billion in March following increased demand for luxury jewellery.

Mr Rupert is the chairman of Switzerland-based Compagnie Financière Richemont, which owns luxury brands such as Cartier and Montblanc. His family has a 10.18 per cent economic interest in the company and 51 per cent of its voting rights.

The company was formed in 1998 from assets owned by Rembrandt Group Limited, which his father founded in the 1940s. Much of his wealth is tied to the company.

Currently, Mr Rupert ranks as Forbes’ 161st-richest person in the world and second in Africa after Aliko Dangote.

Richemont’s shares have surged 19.4 per cent over the past 12 months on the Johannesburg Stock Exchange, according to Billionaires Africa. The surge has contributed to the increase in Mr Rupert’s wealth.

The growth was driven by its jewellery division, which also includes Van Cleef & Arpels, Buccellati and Vhernier.

The group reported €6.33 billion in sales between April and June, a 20 per cent increase at constant exchange rates and 17 per cent at actual exchange rates. Jewellery sales increased by 24 per cent to €4.73 billion during the same period.

Richemont said sales rose across all regions, including Europe, the Americas, Asia-Pacific, Japan, the Middle East and Africa. Its watch business grew by eight per cent to €873 million, while fashion and accessories sales rose by nine per cent to €724 million.

“This set of results smashes consensus,” Luca Solca, the luxury analyst at Bernstein, said, according to Billionaires Africa.

Mr Solca added that the group benefits from selling high jewellery pieces to very wealthy consumers at retail prices ranging from $40,000 to more than $1 million, as well as to the middle class, which buys lower-priced jewellery.

“When spending $3,000 to $4,000, a middle-class consumer is more likely to favour jewellery over a bag, for example, because they can wear a ring, bracelet or necklace every day and it’s seen as having a longer life,” he said.