The purchase comes after the company agreed to buy 25% of the Salobo gold production in 2013.
The previous deal has been amended to include the additional 25% stream.
With this deal, Silver Wheaton will have an added average gold production of around 70,000 ounces a year for first ten years and 60,000 ounces a year over 30 years.
The company expects to produce 43.5 million ounces of silver equivalent production, including 230,000 ounces of gold, increasing to 51 million ounces of silver equivalent production, including 325,000 ounces of gold in 2019.
Silver Wheaton president and CEO Randy Smallwood said: "Salobo is certainly one of the best assets we have ever seen and one that readily lends itself to streaming.
"With over 70% of global silver production sourced as by-product, we continue to believe that the silver market represents the largest market for streaming opportunities."
The company’s proven and probable gold reserves, measured and indicated gold resources and inferred gold resources are estimated to increase by 3.3 million ounces, 0.8 million ounces and 0.4 million ounces respectively.
Considering gold as a percentage, Silver Wheaton’s production is estimated to grow to more than 40% in the next five years.
Vale is preparing to accelerate mill throughput at the Salobo mine to 24 million tons a year.
