Chrome

Chrome is short for chromium (Cr), which is a hard grey metal that can be polished to a high sheen. It has a high melting point, and originates from Chromite, which is the only ore in which chromium is found.

In 2020 South Africa was by far the highest global exporter of chromium ore or chromite, followed by Turkey, Pakistan, Kazakhstan and Albania. It is estimated that 99 percent of the world's chromite is found in southern Africa and Zimbabwe, enough to supply the current demand for hundreds of years. Podiform deposits of chromium ore are open-pit mined whilst stratiform deposits and mined underground.

Chromium can be released into the environment by the burning of natural gas, oil, or coal as well as dust pollution from mining and smelting. It does not usually remain in the atmosphere, but is deposited into soil and water where it can change from one form to another and cause damage to marine life. Chrome can be recycled but not easily and chrome plating of aluminium complicates the recycling process for aluminium, though stainless steel scrap metal is generally recycled.

It is an important and indispensable industrial metal because it is hard as well as resistant to corrosion. It is used in the production of stainless and heat resistant (SHR) steels, where often about 18% is chromium, in nonferrous alloys as well as in the creation pigments and chemicals that are used to process leather.

In general its most commonly recognisable use is in kitchen appliances, food processing equipment, medical and dental tools as well as vehicle fittings such as trims and hubcaps. Chromium in super-alloys (high-performance alloys) are stable at high stress-temperatures, as is Chromite which is used in blast furnaces and brick moulds because it retains strength at high temperature.

Chromium is also important for health. Organ meats, mushrooms, wheat germ, and broccoli are good dietary sources of chromium. Insufficient chromium in the body can result in glucose intolerance.

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