Gold is a precious metal that has been used as currency, jewelry, and decoration for centuries.
Its value has only continued to increase, making it one of the most coveted materials in the world.
Here are some interesting facts about gold, its production, and its many uses!
- Gold is a chemical element with the atomic number 79. This means that gold has 79 protons in its nucleus. It is malleable, shiny, and dense, making it fit for many uses today.
- The price of gold is determined by its purity, which is measured in karats. Pure gold is 24 karats. The density of pure gold is 19.32 g/cm³ or 19 320 kg/m³ (or 0.032127 lb/in³).
- Gold’s chemical symbol, Au, comes from the Latin word aurum, which also gives us the words “aurora” (the dawn of day or morning twilight) and “aurochs” (large extinct wild ox).
- Gold is malleable, meaning it can be easily shaped into different forms. It is considered a transition metal, as it is less dense than most metals and has the properties of both metals and non-metals. It conducts heat and electricity very well, maintaining a high standard of thermal and electrical conductivity.
- Gold can be drawn into a wire of single-atom width. A thin film of gold can be hammered into very thin sheets known as gold leaf, which is often used to decorate objects such as religious icons or paintings.
- Gold is a good conductor of electricity, making it ideal for use in electronics. It is also a great conductor of heat, making it perfect for cooking utensils. The only common metal better at conducting heat is silver, which conducts heat about 20% better than gold.
- Gold is very unreactive and does not corrode or tarnish easily. It will oxidize in the air over several days to form a dull film called a “patina” and can be polished.
- Gold is also a very dense metal, weighing 19 320 kg/m³ (almost twice as much as lead)! If you were to try to float on a pool filled with gold, you would sink right to the bottom!
- Gold is non-toxic and does not corrode, making it a popular choice for jewelry. Many people believe that gold can cure diseases or act as an aphrodisiac (a substance taken to increase sexual desire).
- Gold is one of the most abundant elements in the Earth’s crust. It is believed to have been formed because of supernovas crashing into the Earth billions of years ago. There are also theories that gold can be created in a laboratory, using particles accelerated to high speeds smashing into other metals.
- Gold can be combined with other elements to create alloys that are stronger and have different properties than pure gold. A common alloy is 14 karat gold, which has 10% other metals mixed in with it.
- Gold’s color is what makes it the most valuable and desirable. It does not tarnish or corrode easily, so the metal will keep its appearance for a long time. Gold is often used to make coins because it is very dense and doesn’t corrode.
- People have been mining gold since before the beginning of recorded history. Gold was first mined in Turkey around 6000 BC, and it is believed that the Egyptians were the first to use gold for jewelry.
- Gold mining is difficult because its abundance makes it highly diluted in other rocks and soils, so most gold today is mined through “placer deposits” or “placer mines.” Placer deposits are concentrations of minerals in layers of gravel in rivers or oceans. Gold is separated from the stones, sand, and other materials through a process called “crushing,” when the stones are smashed into smaller pieces by heavy machinery. Crushed stone is then put into pools of water to separate out large pieces of metal that will sink when they are thrown into the water.
Gold has been mined all around the world for centuries. Gold is most commonly mined in California, Alaska, Nevada, Arizona, South Dakota, Utah, Colorado, Idaho, and Montana. The estimated amount of gold left to be mined is about 50 thousand tonnes or 9 million pounds. Gold mining has become increasingly popular because the price of gold has steadily increased since WWII.
Gold nuggets are very difficult to find, but usually, only make up a small percentage of gold deposits that are found in rivers. Most nuggets are found by panning for gold in rivers or using a metal detector. As technology advances, companies are now looking for gold underground instead of on the surface. There are approximately 150 registered mines in the US alone!
Gold is mostly mined by digging it out of the ground and grinding it into dust that is then leached with cyanide to extract the gold. Afterward, the cyanide is recycled and the gold is removed from the solution by precipitating it with an alkali such as zinc or cadmium. Then the newly formed gold-containing compounds are filtered out and melted into bricks. The bricks are then sent to a refinery where they are smelted and poured into brick molds. These bricks are then dried, cleaned, and when necessary, lightly alloyed with other metals to increase their strength. The number stamped on the brick indicates what percent of gold is contained in the brick.
Gold is commonly alloyed with silver in order to create alloys that have both the desired malleability and resistance to corrosion. Gold-plated jewelry is usually made from gold alloyed with silver, copper, or nickel. The amount of gold used in the alloy only needs to be a couple of percent because it will not corrode and therefore, does not need to cover the entire surface. Gold-plated jewelry can also be made from base metals that have been coated with a layer of real gold by using electrolysis.
Gold can be alloyed with as little as 4% silver to make an alloy that is 75% gold and 25% silver, but this will increase the hardness of the gold. On the other hand, making it too soft (lower than 10%) decreases its ability to be worked into thread or wire; 6-10% is ideal. The melting point of gold alloys ranges from 1800°F to 1900°F.
Gold can be alloyed with copper to make red, pink, or purple gold. Red gold is made by adding two parts silver for every three parts copper; this will form an alloy that is 50% copper and 50% silver. Alternatively, copper can be alloyed with silver to make white gold.
Gold is rare yet useful and sought after by many people across the world. It has been used for everything from jewelry and tableware to ships, sculptures, and artwork. Because of its scarcity, once it’s mined out, it has become an extremely valuable item in the world.
The Ancient Egyptians believed that gold was a symbol of eternal life, so many mummies’ coffins have been found lined with gold. In the Middle Ages, people used it for armor and to make weapons because it is one of the few metals that doesn’t rust. The melting point of gold makes it useful in creating coins, so the first gold coins were made in about 635 B.C. by King Alyattes of Lydia (a region that is now Turkey). Gold’s unique yellow color and its distinctive sound, when dropped on a hard surface, make it perfect for making jewelry, chalices, and other fancy objects.
Gold is particularly important in electronics because it does not corrode, and can be drawn into wire easily. It is prized for both its conductive properties and appearance; gold-plated jewelry has some benefits as an electrical conductor, but mostly makes a fashion statement. Because of its conductivity, the microchips in computers and other electronic devices often have gold interconnections.
Gold has been used as money throughout history; even the United States used it to back its paper money. After WWII, however, people began to switch from using gold as a currency to fiat currency because this made trading easier and more efficient.
Gold has also been used throughout history in various chemical reactions. For example, it is the only metal that reacts with concentrated acids to form soluble compounds. The acid does not even have to be dilute hydrochloric acid; gold will react with nitric acid and aqua regia (nitro-hydrochloric acid) as well! In many of its compounds, gold exhibits a characteristic red color. This property makes it useful for coloring glass and ceramics. In fact, that’s where most of our gold is used now!
Gold is a rare and valuable metal that has been used for jewelry, coins, armor, and other objects throughout history. It is prized for its color, conductivity, and resistance to corrosion.
Gold is also important in the electronics industry because it does not corrode.
Although people have stopped using gold as money in many places around the world, it still retains its value as a precious metal.
In fact, most of the gold mined today is used in various electronic devices or in the glass and ceramics industries.
Gold can be found in many different places around the world, especially in so-called “virgin deposits,” which have not been exposed to the atmosphere for long periods. However, most of the gold mined today comes from mines and other excavated areas that produce large amounts of gold.
Although mining is a dangerous and expensive process, it remains one of the most important ways to collect gold. Gold’s unique properties have made it useful throughout history, especially in the electronics industry.