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Exploration Mining facts

Copper, Gold, Indium, and Canadian mining in our lives

Never before in history has technology played such an integral role in our daily lives.

From Zoom meetings on our iPads, to multi-monitor at-home workstations, to celebrating a holiday with our loved ones through a screen, our devices are our access to the world.

Canadian mining provides the materials that make the devices the world uses to communicate.

In 2019, Canada mined over 577,000 metric tons of Copper. Many of the largest Copper mines in Canada, such as Teck’s Highland Valley Copper and Newcrest/ Imperial Metal’s Red Chris mine, are located in BC .

Copper is used in computer chips, car batteries, and electrical wire. A smartphone handset consists of approximately 40% metals, predominantly copper, gold, platinum, silver and tungsten.

Gold is mined in 9 Canadian provinces and territories, and is the highest valued commodity produced in Canada by value of production. Demand for gold production continues to grow each year.

Most gold is used for jewelry making, but approximately 7.6% of the demand for gold is for use in technology applications, mostly as a component of microcircuitry in a range of electronic products. Gold is also an essential element used in health care treatments and applications, including cancer treatment and rheumatoid arthritis treatment.

Indium is “the everyday metal you never see”. According to the USGS, Canada is one of the top six producers of indium in the world. In fact, Teck is a key contributor as one of the largest single source producers of indium in the world.

So what is Indium used in? This is best explained by a US publication, Mining News North:

“If you are reading this article on your computer, tablet or phone, you are almost certainly looking through indium, and if that devise happens to be a touchscreen, you have the unique properties of this critical mineral to thank as you scroll down to read more about indium and where it can be found in Alaska.

This is because indium-tin oxide is used as a transparent conducting film applied to virtually every flat-panel display and touchscreen on the market. This thin coating transforms incoming electrical data into an optical form.

When it comes to the combination of characteristics required for this widely used application – transparency; electrical conductivity; strong adherence to glass; corrosion resistance; and chemical and mechanical stability – indium-tin oxide has no equal.”

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Mining facts

Mining’s Future in a Green Economy

Michael Goehring, CEO, Mining Association of BC discusses mining’s important role in the green economy.

credit: Mining Association of British Columbia

“BC is a hotbed of innovation, so our industry is working closely with BC’ tech sector so we can conserve more, waste less, and reduce our environmental footprint.”

“The minerals and metals that BC produces – copper, silver, gold, steel-making coal, aluminum, molybdenum – they are all essential to a low-carbon future. An electric vehicle takes four times as much copper as a traditional internal combustion vehicle. You can’t make solar panels without silver. And you can’t transmit power from solar panels without copper. Our mineral sand metals are essential to a low carbon future.”

“We now know, in BC, our steel-making coal – which is critical to renewable energy infrastructure – wind mills, for example, has half the GHG emissions intensity as our competitors in Australia. BC’s Copper has about 40-50% less GHG emissions than copper from Chile. Our industry has been reducing its GHGs for several decades. The real driver is our clean energy, driven out of our hydroelectric assets.”

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Mining facts

Tailings – What are they and what is in the Mount Polley tailings?

First, what are tailings?

Tailings are essentially crushed rock, and are the leftover material after the minerals containing the “elements of interest” have been removed. At Mount Polley the elements of interest are copper, gold and silver. The minerals containing the copper, gold and silver are released by crushing and grinding the mined rock down to sand and silt sized particles.

At Mount Polley, a process known as flotation is then used to separate the important copper-bearing minerals from the rest of the crushed ground rock. The remaining crushed rock is considered waste (gangue) and is what makes up the tailings. No cyanide is used at Mount Polley.

Read more about Tailings on the Mining Association of BC’s website here.

What is the in the Mount Polley tailings?
At Mount Polley, the valuable elements are copper, gold and silver and they are found most commonly in the sulphide minerals, chalcopyrite and bornite. The leftover minerals found in the waste are piped as a slurry with water to the tailings storage facility. [ref: Community Updates 2017 Issue 3; 2016 Apr Issue 2]

The rocks that are mined at Mount Polley are around 200 million years old and represent ancient volcanic rocks and magma that intruded into these rocks. The intrusive rocks host the copper, gold and silver mineralization.

Let’s talk rocks!
The rocks which host most of the ore are made up primarily of the minerals orthoclase (potassium feldspar), albite (sodium plagioclase), magnetite (iron oxide), Ca-plagioclase (calcium plagioclase), diopside (pyroxene), garnet, biotite (mica), epidote and calcite (calcium carbonate). These minerals are all common rock-forming minerals, and represent 90% of what ends up in the Mount Polley tailings pond.

Of the other 10 percent, most are also common minerals, with a minor amount of sulphide minerals, including a little bit of chalcopyrite (0.17%) that didn’t get captured in the mill and a small amount of pyrite (0.04%).

What is unusual about Mount Polley is that, when compared to many other copper deposits (and the reason why these tailings are considered by geochemists to be chemically quite benign) there is very little pyrite (iron sulphide) and a fair amount of calcite (calcium carbonate) in the tailings.

Due to this, Mount Polley’s tailings do not generate “acid rock drainage”. This is the process that happens when sulphide minerals, especially pyrite, are exposed to the atmosphere and react to form sulphuric acid, which then can leach metals out of tailings and lead to metal mobility and potential contamination.

Mount Polley’s tailings do not have this “acid rock drainage” problem, as there is very little pyrite, and calcite acts as a neutralizing agent if any of the minor amounts of sulphide in the tailings breaks down. The vast majority of the rest of the minerals in Mount Polley’s tailings does not react easily with air or water, and are very similar to natural sand.