Living silver. How does mercury help extract gold from the depths of the planet and why is it dangerous?

Mercury is a very dangerous contaminant that has long been used to extract gold. Mercury’s unique ability to bond with gold has made it an incredibly useful tool in the mining industry, IFLScience writes, but this ancient practice also comes with serious dangers.

So how exactly does mercury help extract gold from the depths of the planet, what are the consequences of such mining and why was this metal called mercury? Researchers answered these questions.

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BC in Egypt and its surroundings. Since 1500, mercury has been actively used as medicine, despite its toxicity. The name “mercury” comes from the Latin argentum vivum, meaning “living silver” – this indicates the liquid state of the metal and its color.

Researchers also found that mercury dates back to B.C. He believes that precious metals such as gold and silver have been mixed and used as mining tools since 750 BC. Different methods have been used to extract minerals over time and around the world, but the historical use of compounding bears significant similarities to the technology used today.

How does mercury help extract gold?

What is the secret of mercury and how does the liquid metal help extract gold nuggets from rock? According to scientists, this process is usually carried out in rocks where the broken pieces of gold are extremely small, and therefore other methods of extraction will not be effective.

Liquid mercury mixes with the rock and dissolves bits of gold, leaving the rest of the rock to form an alloy of gold and mercury known as gold amalgam. The alloy is then separated from the unreacted mercury; This process is done by squeezing the liquid through a piece of porous material such as suede.

Essentially, the filtered liquid is a pure form of an alloy of mercury and gold. Then comes the next stage of converting the amalgam into pure gold. To do this, the alloy is heated to a temperature higher than 356.7°C, where mercury turns into a gas and remains gold, since its boiling point is much higher – 2836°C.

Dangers of using mercury

Scientists state that this method is effective, but produces a highly toxic form of vaporized mercury, which can cause some health problems. For example, damage to the respiratory, gastrointestinal and central nervous systems. Symptoms of inhaling mercury vapor include:

• difficulty breathing;
• vomiting;
• headaches.

Note that this gold mining process is no longer used on an industrial scale, but is still used in artisanal and small-scale gold mining. A 2018 study found that these practices are now the largest source of mercury pollution on Earth, releasing more than 1,000 tonnes of evaporated mercury each year.

Researchers say 10 to 19 million people in more than 70 countries use mercury to extract gold, and its fumes affect not only the health of miners but also the health of ecosystems, water resources, soil, wildlife and food.

Previously Focus He wrote that scientists explained what would happen if you touched mercury with your bare hands.