Even when worn in hot springs or exposed to sweat, gold and platinum won’t lose their color. They are metals that are extremely resistant to corrosion and acid and alkali. Why then does jewelry made of gold and platinum still change color despite the fact that these two metals do not oxidize? This time, we’ll explain to you why jewelry oxidizes and changes color as well as how to handle it safely. I hope you will be able to carefully guard your favorite jewelry after reading it and use it for a very long time!
Will gold and platinum oxidize?Platinum and gold are regarded as very stable materials. There is no other solution besides “Aqua regia” that can dissolve them because of how stable they are. (a special solution made by mixing concentrated hydrochloric acid and concentrated nitric acid). They won’t experience oxidation because it doesn’t interact with other substances. They are known as precious metals because they are extremely rare, expensive, and will not rust or oxidize. Additionally, although there is less discoloration the higher the purity, the higher the purity also means that it is softer, more easily deformable, and heavier. The density of platinum and gold with a weight of 20 grams per cubic centimeter are quite high. Therefore, these two metals are not suitable for use in jewelry that needs to be crafted in detail.
The purity and color of goldThe unit of gold purity is “k” (carat), and 99.99% purity is marked as k24, and it can also be expressed as 24k or 24k gold. K22, K20, K18, K12, and K10 show a decreasing trend in the gold content. When it falls to k10, it means that less than half of the product’s weight is made up of gold. The color of the jewelry will also change differently when gold is combined with various metals. For instance, rose gold is created by combining red metals like copper, while white gold is created by combining white metals like nickel or silver.
The purity of platinum
The purity of platinum is measured in “pt.”; 1000 pt is the amount of pure platinum. 90% of the platinum content is denoted as pt900 and 95% as pt950. It costs more to produce when the purity is higher. Among the platinum metals, palladium is the one that is most frequently used to create alloys.
Why does jewellery change colour?
The most frequent reason for discoloration is when the jewelry comes into contact with chemicals like detergents, shampoos, or ingredients in hot springs, as well as oxygen, sweat, sebum, or other substances.In everyday life, gold or platinum won’t change color. However, as was already mentioned, gold and platinum are typically alloyed with other metals because, depending on their purity, they are more prone to deformation. Even jewelry made of gold and platinum will change color due to the oxidation of the other metals used in the jewelry’s composition and the decreased amount of gold and platinum in the piece. It is advised to choose K18 gold products or platinum products above pt900 if you don’t want your jewelry to change color easily.
My jewelry has oxidized and changed color, what should I do?
If the jewelry on your hand has changed color, what should you do and what are the precautions?
Jewelry can be effectively protected from discoloration by diligently wiping with a soft cloth or cleaning with a neutral detergent. The best course of action is to wash the jewelry as soon as possible after each use because sweat or sebum residue on it can easily cause oxidation. It is the best way to remove the chemically reacted portion of jewelry if the color has changed. Hardware stores sell abrasive cloths for grinding precious metals, and you can use abrasive cloths to gently remove the discolored areas.
Note: Please confirm the engraving of the jewelry before maintenance!
Jewellery is made from a variety of materials and is processed in a variety of ways, so cleaning procedures and safety measures also vary. Please remember that gold and platinum are incredibly soft metals, despite the impression that they are strong. Its tensile strength could be impacted as it becomes thinner and thinner. Pay close attention to the fact that marks like GF (gold-clad), GP (gold-plated), PP (plastic electroplating), WG (rhodium-plated), and others mean that the jewelry has been polished and electroplated. It might result in the plating process peeling off. Finally, if the jewelry has gems set into it, take extra care when grinding so as not to damage the gems. In the case of extremely pricey or precious jewelry, it is recommended to consult the store where you purchased it directly.