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The Golden Element
Gold is a chemical element. The symbol for gold is AU. The symbol lends its name from the Latin word for gold, aurum.
Gold is 79!
No, gold isn't going to turn 80 next year. 79 is the atomic number associated with gold. The atomic number is simply the number of protons that are found in the nucleus of an element. You can also call this the proton number.
Gold has long been used as a material for jewelry. The malleable properties make this material great for use in all kinds of different jewelry designs. Gold alone is too soft for use in jewelry. It is often alloyed with different metals to create a material suitable for jewelry.
Pure gold is referred to as 24 karat (24k). There are no other metals added to this, it is gold through and through! You may wonder how certain karats of gold are figured. Well, wonder no more! It is no more than a simple arithmetic. Lets take a very common karat of gold, 14 karat. To figure the percentage of gold in this material divide 14 by 24. 14 in this case is the karat weight we would like to know the percentage of gold. 24 is the karat weight of pure gold. The answer is 58.3% gold!
Here are a few different karats of gold and their % of actual gold:
- 22k Gold: 91.6% gold mixed with other alloys
- 18k Gold: 75% gold mixed with other alloys
- 14k Gold: 58.3% gold mixed with other alloys
- 10k Gold: 41.6% gold mixed with other alloys
For a piece of jewelry to be considered gold, in the United States, it must be at least 10k. Anything lower than this amount cannot be sold as a gold piece.
Rose/Purple Gold Ring
Colors of Gold
We know, we know! Gold is yellowish in color! However, it can be mixed with different materials to alter it's appearance. An example of some materials that are mixed with gold are copper, nickel, palladium and aluminum.
- White Gold is a popular choice for colored gold. This material is often made by mixing gold with different metals such as nickel or palladium. The result is a white material.
- Rose gold, or red gold, is another combination that is created. This pinkish, red color can be obtained by mixing gold with copper. Some different karat weights of rose gold feature a small amount of silver.
- Green gold is an alloy that is obtained by adding silver. The amount of silver added will affect the end color.
There are a few exotic gold alloys that are used in special cases. Purple gold is created by adding aluminium to gold. This creates a unique purple hue. Blue gold can also be created by adding indium. Both of these materials can be brittle and are used in carefully executed jewelry designs.
Gold Color Poll
What would be your favorite color of gold?
Out of this world!
During Earth's formation, the planet was very hot! It was so hot in fact, that it was a molten object! Molten iron sank to the core of the planet bringing with it many of our precious metals. It is thought that the majority of gold we have on the surface today was brought to us by meteorites. Over the course of Earth's existence, we have been bombarded with many of these extra-terrestrial objects. These objects bring with them many different materials such as water, gases and even metals like gold!
Ductile and Malleable!
Gold is very ductile. Of all of the metals, gold is the most ductile. You may be sitting there thinking, well what does this mean? Well, have no fear! Here is an example that will help illustrate this unique property. Gold can be drawn out into wire. In fact, 50 miles of gold thread can be drawn from only 1 single ounce! You can say gold preforms well under pressure!
Gold is also very malleable. It can be hammered and pressed into different shapes and formations without breaking or cracking. This is one reason why it works very well for jewelry. That same ounce from earlier can be shaped into a sheet that is about 300 square feet! We can press gold sheets so thin, you can see through it! Talk about transparency!
A noble metal
Gold is truly a noble metal. We don't mean it has high moral principles and ideals. Being a noble metals simply means it is resistant to corrosion or oxidation in moist air. There are different standards for classifying a noble metal in chemistry and physics. The common noble metals, in electrochemistry, are listed here:
In physics terms, which are much more strict, there are only three noble metals. These are Gold, Silver and Copper.
Gold Bars and Coins
Gold has long been used as a form of trade or investment. Gold is made into different sizes of bars from 1 gram to 100 troy ounces.
Gold was once used as a standard for monetary trade. This was known as the gold standard. As of today, there are no countries that use this standard. The last currency to use this as a standard was the swiss Franc. About 40% of the currency was backed in physical gold.
Gold coins are still minted. Most coins are minted solely as a collector item or for gold bullion. Bullion coins or bars are strictly worth the value of the material. These would not be considered collectors coins. There are certain factors that can determine the value of a coin. These can be the amount minted, the condition of the coin and the year it was minted. The 1933 run of Double Eagle coins featured about 445 thousand coins. Most of these were melted down and very few survived. Of the survivors, one was auctioned at Sotheby's for an astonishing $7.5 million!
Ocean of Gold
The world is about 70% water. Therefore, we should expect that most of the world's gold is in the vast oceans. In fact, about 10 times more gold resides in the oceans than has been mined in history. They are truly oceans of gold!
Gold to Cure Your Cold?
Gold has long been used as an additive for medicine. It may be one of the earliest forms of medicine. Egyptians used it as a healer of body, mind and soul. Gold is natural, non-toxic and our bodies are able to endure it very easily! Gold is often used in a substance known as colloidal gold. Fine elements of gold particles are suspended into liquid and this is used for a variety of different treatment options.