(IDEX Online) - Dominion Diamond Mines, which filed for insolvency in April, has sold its Ekati mine, in Canada after receiving a solitary bid.The buyers are part of The Washington Companies, a privately held conglomerate based in Montana, USA, that bought Dominion in 2017 for $1.2bn. Toronto-based Dominion, the world's third largest producer of rough diamonds by value, shut Ekati (pictured) in March because of COVID-19.The mine has been bought by Canadian Diamond Holdings, L.P. and CA Canadian Diamond Mines ULC in a $146m deal that is set be signed in November.Dominion also holds a minority interest in the Diavik mine, but Rio Tinto, its joint venture partner, vetoed selling it. The two companies are currently locked in a legal battle over the management of the mine and production targets.Ekati became Canada's first diamond mine when it opened in 1998 about 300km northeast of Yellowknife, near Lac de Gras, Northwest Territories.