It said its subsidiary Ivanplats had reached agreements, flagged earlier this year, with Orion Mine Finance and Nomad Royalty Company for a $200 million gold-streaming facility and a $100 million palladium and platinum-streaming facility.
Nomad, which is circa 70% owned by Orion, will pay $75 million in exchange for 37.5% of the gold produced to 131,250 ounces, then 30% until 256,908oz are delivered and 1.875% thereafter.
Ivanhoe said the offtake arrangements, subject to a definitive agreement, were with South Africa-based producer Northam Platinum and Heron Metals, a joint venture with commodities trader Trafigura.
It said the proposed offtakes covered 100% of Phase 1 PGM concentrate production, which was expected to be more than 40,000 tonnes per year containing six payable metals, including palladium, rhodium, platinum, nickel, copper and gold.
"The stream financing agreements, which represent a small fraction of Platreef's incredible resource base, and accompanying offtake arrangements are critical milestones in the progression to commercial production for Ivanplats," Ivanhoe president Marna Cloete said.
The company's battery-electric mining fleet was due to arrive on site early in 2022.
Cloete saw the first-phase 700,000tpa operation as a starter operation, with expansions up to 12Mtpa "and beyond" to position Platreef among the world's largest and lowest-cost nickel and PGM mines.
Ivanhoe is using a similar phased approach to its new Kamoa-Kakula joint venture copper mine in the Democratic Republic of Congo.
The company said it could now focus on finalising a senior debt facility for up to $120 million, which was anticipated to be used once the stream facilities were fully drawn.
"Ivanplats remains flexible to raise additional debt or equity at a later date, and has pre-agreed with the Stream Purchasers the intercreditor arrangements for any future senior debt," it said.
Platreef is owned 64% by Ivanplats, 26% by broad-based black economic empowerment partners and 10% by a Japanese consortium.
Ivanhoe shares rose 0.5% yesterday to C$10.09, near a one-year high and capitalising the company at $12.2 billion (US$9.6 billion).