Harry Winston Diamond Corp., a Toronto-based diamond mining company, is selling the brand seven years after it bought it, for 6.3 times the acquisition price, to raise funds to reinvest in upstream assets and development.

Harry Winston was acquired in 2006 by the-then Aber Diamond Corp., which later changed its name to Harry Winston Diamond, for $157 million. Swatch is paying $750 million for the operation and assuming $250 million of pro-forma net debt.

"At the time that we purchased the Harry Winston brand, resource investment opportunities for diamonds were rare and expensive," said Harry Winston Diamond Chairman and CEO Robert Gannicott. "Today there is a range of diamond resource opportunities while the value of heritage luxury brands has increased dramatically."

The deal comes just over two months after Harry Winston Diamond agreed to pay $500 million for BHP Billiton Ltd./plc's Ekati diamond mine in Canada. Diamond mining has fallen out of favor with global mining companies, including BHP Billiton and Rio Tinto Group, which have struggled to make targeted returns from the operations and to realize economies of scale from the niche operations.

The deal "leaves us well equipped to realize upstream opportunities in an environment where cash has become a strategic resource while preserving and expanding our relationship with the downstream diamond business," said Gannicott. Harry Winston Diamonds said it will receive $750 million of cash from the deal. Its market capitalization was C$1.21 billion ($1.23 billion) based on its Friday closing price of C$14.27.

The purchase of the Harry Winston brand is Swatch's biggest deal for more than a decade and builds on a small stable of luxury brands that include Breguet, Blancpain and a license to make watches on behalf of Tiffany & Co. Swatch's only other jewelry brand is Léon Hatot.

Swatch had been widely expected to make acquisitions having accrued a cash pile of Sfr1.13 billion ($1.24 billion) by the end of June. Biel, Switzerland-based Swatch last week said it made Sfr8.14 billion of revenue in 2012, a 14% increase over 2011, and expected sales to grow again in 2013.

"Harry Winston brilliantly complements the prestige segment of the group," said Swatch Chairwoman Nayla Hayek.

Harry Winston Diamond will change its name to Dominion Diamond Corp. once the transaction completes and said it was investigating the possibility of launching a diamond polishing joint venture with Swatch.

Harry Winston Diamond took financial advice on the deal from Rothschild, which was also one of its advisers during its acquisition of the BHP Billiton diamond mine.

Swatch has a market capitalization of Sfr26.5 billion. Its shares traded on the Swiss exchange Monday at Sfr507.5, up Sfr15.20, or 3.2%, on their Friday close.