But some critics wonder how firm those promises are.
The commitment to supply rough diamonds came during the close of two weeks of Mackenzie Valley Environmental Impact Review Board hearings. De Beers fielded questions from experts about its proposed underground diamond mine.
De Beers Canada president Richard Molyneux repeatedly stated the company intends to "maximize" the number of Northern and aboriginal employees.
The company's predicted targets are: 40 per cent Northern and aboriginal workers during construction; 60 per cent during operation; and, 60 per cent during closure.
However, Molyneux refused to turn these predictions into actual targets.
"They don't seem to want to make these commitments in writing," said Kevin O'Reilly of the Canadian Arctic Resources Committee.
But Molyneux brushed aside the notion that solid numbers translate into more solid commitments.
"We are genuinely saying we'd like to see operations have the highest amount of aboriginal and Northern people," he said.
Later, when asked, he agreed that finding a steady stream of Northern and aboriginal workers is a concern, especially with two existing diamond mines in the area.
"Absolutely yes," he said. "It really does require a lot of crystal ball gazing to sensibly and realistically make those estimates."
David Gilday of the department of Education, Culture and Employment asked if De Beers has a method of verifying whether employees really live in the North.
Gilday then admitted the government's medicare cards aren't a reliable test which caused Molyneux to wonder whether the GNWT is equipped for its side of the bargain.
"You have government people asking for industry to provide the method of determining where people actually are living," said Molyneux after the hearings.
"That leaves me with a concern about capacity in all sorts of areas."
Fund for communities
De Beers also promised to set up a community-controlled fund for socio-economic needs.
And the company's human resources plan includes building learning centres to teach literacy and trade skills in five primary communities over a five-year period. The use of these centres is limited to De Beers employees, he said.
"It's a huge commitment," said Gilday.
But O'Reilly was disappointed De Beers didn't attach dollar figures to any of these commitments.
"I had hoped for some specific targets, specific contributions to programs... I don't think the company has quantified (economic benefits) in any way."
O'Reilly also said the government should set aside funding for groups to wade through De Beers 5,000-page environmental impact study.
This was a concern echoed by aboriginal leaders at the hearings.
Florence Catholique of the Lutsel K'e Dene Band said they don't have the resources to gain a complete understanding of it. She wanted to make clear her silence at the sessions wasn't interpreted as acceptance.
"We need to be able to make decisions based on good information," she said.
Other people move can move away when the mine closes, she said. "But we, the people who live here, are left to bear whatever happens."
More public hearings are planned for March.
De Beers' commitment on diamonds and Northern hires will be the focus of socio-economic negotiations with the territorial government that begin this week.
Jim Antoine, minister of Resources, Wildlife and Economic Development, applauded the company's recent decision. He said the GNWT will continue to insist that Northern diamonds go to the NWT's diamond manufacturing industry.