Gold is considered a valuable metal that does not change color over time, but this information applies to pure gold to which no other metal has been added. In the gold market today, there are many gold products and alloys that have been mixed with other metals that change color over time, such as nickel and iron. A percentage of these metals must be added for gold to gain the advantage of resistance, as it is a very flexible element.
18-karat gold products contain 75% gold and 25% other metals such as nickel and copper, which affect the color of the original gold, causing its color to turn pink due to these metals. The presence of these metals may cause gold to change color after a long period of time, either due to an increase in their percentage, storage methods, or incorrect use. As for 21-karat gold, it contains 87.5% gold, which makes its color more similar to the color of the original gold, which is yellow. Therefore, it is considered more flexible and maintains its color more. It is also widely used in the jewelry and alloy industry, in addition to medical and industrial uses. The higher the purity of gold, the less its color changes over time.
Does gold change color with fire?
Pure gold does not change color when exposed to fire, but rather melts. This is what distinguishes it from other metals, as it is easy to melt to reshape it without changing its color and shine. If you expose gold to fire, you will notice that it will not ignite or burn. It will either melt or become dark in color. This is due to the abundance of copper or iron elements.
Does gold change color with water?
Pure gold does not change color with water, but because gold is mixed with other elements to become harder, its constant exposure to water can cause it to lose its luster in the long term.
How does gold regain its color and shine?
There are many different ways to restore the color and shine of gold, but they require experience to avoid damage to the gold pieces. It is preferable to go to gold stores to renew its color and shine. But here are some easy and safe ways at home:
Dishwashing soap: Put a drop of soap for every half cup of warm water, then place the gold pieces in the mixture for five minutes, then wash them with water and dry them with a soft cloth.
Toothpaste: Put a little bit of the paste in a cup of warm water and place the gold pieces in the mixture for five minutes, then wash and dry them with a soft cloth.
Finally, gold remains one of the unique and precious metals that does not change color easily, and it maintains its shine for a long period of time. However, preserving the beauty and quality of gold requires handling it with caution and taking care of it in correct and gentle ways so that it lasts longer.