Under revised terms, Osisko has immediately advanced US$2.5 million of the remaining deposit for the metals stream, with a further $7.5 million to follow over the next 12-18 months based on achieving milestones.

In exchange for the accelerated payment schedule, Osisko has reduced the total deposit payable from $40 million to $35 million.

The stream percentage will remain 18.5% of gold output capped at 105,000oz, after which the stream will reduce to 9.25%. Osisko will also continue to pay 30% of spot, capped at $600/oz.

The silver stream was changed from 75-85% with no change to the ongoing production payment of $4/oz.

"This transaction provides Aquila with the certainty of funding necessary to enable us to continue to advance the Back Forty project towards construction," said CEO Barry Hildred.

While providing the company with capital to continue building on recent positive permitting developments, the stream amendments also provide it with flexibility to advance Back Forty "on a schedule that reflects anticipated permitting, engineering, and financing timelines".

The company also received a shot in the arm in the form of a US$685,000 Canada Revenue Agency tax refund, boosting the treasury to $3.19 million.

The US$294 million project is now shovel ready and contains proven and probable openpittable reserves of 11.65 million tonnes. The mine plan calls for producing 512Mlb zinc and 468,000oz gold at average reserve grades of 6.7% and 4.3g/t, respectively, over a seven-year mine life.

An August 2018 feasibility study also outlined copper production of 51.1Mlb over the project's life.

Shares in the company (TSX: AQA) are down 20% over the past 12 months at C16c, which capitalises it at $54 million (US$40 million).