Copper coins aren't especially good either, because when they oxidize they will gain some weight from the extra oxygen atoms. So if the weight of a copper coin will depend on how old it is and how long it's been sitting out in the air and turning into copper oxide.
If you want a currency to be based on the weight of coins which is really the only option this is bad news. So gold is rare, has a fairly stable volume, and doesn't rust away. This makes it a useful currency and so it was our primary currency for thousands of years actually until the s when President Nixon stopped the direct link between the value of the US Dollar and the value of the US gold reserves. You might have noticed that I have used iron instead of aluminum as a counterexample to gold.
Humans have only been able to isolate aluminum from bauxite ore relatively recently, so it was not around in ancient times to compete with gold. If it had been, it might have actually fared quite well -- aluminum is a very handy metal that is harder and lighter than gold, so it makes better tools and weapons. It's also not terribly common -- most of our aluminum comes from a few mines in Australia, I believe. But aluminum does oxidize although only very slowly so gold would still have the upper hand there.
This is a very interesting question. Gold is relatively rare in the earth's crust, and particularly because of its value in making jewelry, it has always been worth a lot of money. Aluminum is very common , and is nowadays, easily formed as the pure metal, so it is not very cheap. However, about years ago, the current process of extracting aluminum from its oxide did not exist, and it was actually more expensive than gold.
So it is important to recognize that the process by which an element is obtained plays a big part in what it costs. Rarity is definitely one issue. H 2 O is not very expensive because there is a lot of it around. Silver and Gold on the other hand, like, say, diamonds are very rare. On top of that, the usefulness of a substance makes its price high. Au gold is very useful because it has some excellent chemical properties very inert and also its malleable and can be worked as body decoration rings and bracelets etc.
Diamonds have industrial use because they are very hard and are good abrasives. So the common elements of rarity and usefulness to humans make for their great worth. Al aluminum is all over the place The price of metals depends on their value to humans, their availability, and how difficult it is to extract them.
Gold has always been valued because it is pretty; it does not tarnish, so you can make statues and jewelry and it does not turn black with age; it is soft so you can mold it, and it melts fairly easily. It has been used in jewelry and worship for thousands of years. Top Searches Sensex. Paytm IPO. Bank Holidays in November.
This story is from May 22, Barring currency, if there could have been any indicator to measure wealth in the world, it would definitely have been Gold. Gold is undoubtedly a precious metal for which there have been wars also. This natural resource has always fascinated everyone and has managed to retain its importance over centuries.
People who understand metals will know that gold is not a rare metal, but it's difficult to find and extract the same in large quantities with pre-industrial technology. Price of Gold is not set by any organization, but it depends upon the cost of producing it extracting it from the ground and then purifying it and how people are willing to pay for it.
Gold, unlike many other metals, is relatively expensive to produce, thus making the base price fairly high. If a lot of people wish to use gold and are looking to buy it, they will have to compete with each other for it, which will ultimately result in a price rise. If not there is not much demand for gold, the price will be near the actual cost of production. Aluminum is a lot more commonly found in the earth's crust than gold, thus it is cheaper to produce. Download PDF zip file.
A steel sculpture surrounded by skyscrapers. Maybe not. Iron, a transition metal with 26 protons, is the tenth most abundant element in the universe. Its chemical symbol is Fe, from the Latin word for the metal, ferrum. When you consider the entire planet from core to mantle, iron makes up In early history, pure iron was only found on Earth in iron meteorites with up to 90 percent concentration of the metal. Beads of meteorite iron dated to BC have been found in Egyptian tombs.
Assyrian records show that iron was eight times as valuable as gold before people learned, around BC, to smelt iron ore to produce metallic iron. The Iron Age started about — BC, when iron became more inexpensive than bronze. Steel—a mixture, or alloy, produced by the addition of carbon and oxygen to metallic iron—is harder, more flexible, and less brittle than iron.
Precursors of steel were probably made accidentally by mixing molten iron and charcoal in a smelting fire, producing a stronger alloy. The cast iron alloy had more strength than iron but was very brittle; the wrought iron alloy contained less carbon and was malleable but not as strong as cast iron.
In , Henry Bessemer created the extremely strong, flexible, and durable steel, which has carbon content between that of cast iron and wrought iron. Additional elements may be added to steel to vary its properties.
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