Why Will 925 Silver Turn to Green or Black? And How to Clean It?

Why Will 925 Silver Turn to Green or Black? And How to Clean It?

What is 925 Silver?

Sterling silver is the content of metal silver close to 100%. It is an inert metal, and the special affinity of silver and sulfur, in the air can slowly generate silver sulfide and make it turn to black, make it impure. Silver is easy to mix with platinum and other metals in nature, so the sterling silver in life generally refers to 99.99% silver or 92.5%, that is 925 Silver.

The hardness of Silver is about 2.7, relative density is 10.49. The 100% silver is soft and scratches easily, that is the reason why not suitable for elaborate craft requirements, as well as more and more rich and exaggerated modeling requirements of modern fashion accessories. In addition, 100% silver is easy to turn dark and lose luster. Therefore, in 1851, Tiffany launched the first set of silver containing 92.5%, 925 silvers quickly became the main force of silver jewelry and became the international standard to identify whether silver jewelry is sterling silver. This alloy containing 92.5% silver and 7.5% copper is called standard silver internationally. Which can improve 925 silver shine, brightness, and hardness.

Silver ion in the silver jewelry has a certain health care effect on the human body and can play the role of sterilization and recovery of wound healing.

Why My Silver Jewelry Turning My Skin Green? And How To Avoid It.

 

Most people may meet this problem frequently, but they do not know why it happens. This phenomenon does not mean the silver is fake or of bad quality. This is a normal reaction to wear copper jewelry over a long period of time. It will return to normal once you stop wearing copper jewelry, and it will not impact your skin health. The main reason is the copper. Because 925 Silver has 7.5% copper, the natural acidity of human sweat and other chemicals used on the skin (such as soaps, lotions, and cosmetics) can react with copper. This reaction causes green rust to form on the surface of the copper and transfers color to the skin. But this reaction will not happen to everyone’s.

 

Why will my Silver Jewelry become black?

  1. Silver oxidizes naturally in the air to form a silver oxide, which will become brown or grayish black. If you are in an environment where the air has pollution, it contains some acidic in the air like hydrogen sulfide, the silver will react with the sulfur in the air to produce silver sulfide.
  2. Human sweat contains sulfur, but everyone's physical conditions are different, so everyone wearing silver jewelry will have different results. Some people's body fluids contain high levels of acid and sulfur, which will lead to the blackening of the silver jewelry. And there is another situation: Our muscles produce more hydrogen sulfide (Hydrogen sulfide is produced by muscle cells and has been linked to diseases such as immune regulation, cancer, and high blood pressure.[1] ) when our body is engaged in an immune response. When people sick, the immune system will protect their body, there will be a lot of immune reactions, producing more hydrogen sulfide, which will make the silver obviously black.
  3. If the usual contact with the items containing acid and sulfur is relatively high, will also lead to silver blackening. For example, smoking all year round, wearing perfume, wearing heavy makeup, often using sulfur soap, and taking baths in hot springs will affect the color of silver jewelry.

 

How to Clean When The 925 Silver surface becomes green or black?

  1. There is a special cloth for whipping silver which is called ‘Silver Polishing Cloth’ you can buy from amazon, or Moissanite Corp will give some free Silver Polishing Cloths when you purchase some 925 Silver jewelry from the official website. (Attention: The Silver Polishing Cloth contains silver maintenance ingredients, cannot be washed.)
  2. You can also clean the 925 Silver with toothpaste. It is best to use transparent jelly toothpaste, do not use the toothpaste containing particles, because it may damage the surface of the silver decoration. When cleaning, do not add water first, directly with a cotton cloth dipped some toothpaste to wipe the silver, then you will find that there are black stains on the cotton cloth. After wiping, wash the residual toothpaste with clean water.
  3. If the step 1 and 2 do not work, then you can buy a special silver jewelry cleaner, to follow the instructions to clean them. But this kind of detergent has a certain corrosive, should not be used frequently.

 

 

Reference

Nahzli Dilek, Andreas Papapetropoilos, Tracy Toliver-Kinshy, Csaba Szabo, November 2020, “Hydrogen sulfide: An endogenous regulator of the immune system” https://www.sciencedirect.com/science/article/pii/S1043661820314274

 

 

[1] Nahzli Dilek, Andreas Papapetropoilos, Tracy Toliver-Kinshy, Csaba Szabo, November 2020, “Hydrogen sulfide: An endogenous regulator of the immune system”