Silver turns black when kept in the air because it reacts with sulphur compounds such as hydrogen sulphide (H2S) present in air. The phenomenon is called corrosion and, for silver in particular, is called tarnishing. The black substance formed is silver sulphide.
 
This is a common issue with Silver, even British hallmarked 925 solid Silver can tarnish, it's not a fault, it's a natural occurrence. It is common and certainly not a sign there is a quality issue with your Sterling Silver and can infact be used to provide a decorative contrast against polished Silver to highlight detail, but, how can we prevent it from happening?
 
Sterling Silver is an alloy and is created when copper is added to pure Silver in order to make the resulting metal more durable and less soft. Usually, Sterling Silver has a purity of 92.5%, which is what the 925 stamp indicates (925 parts per 1000) meaning that 7.5% of the alloy is made of copper and other metals (eg. zinc).
 
Copper oxidises when exposed to the atmosphere especially when there is high humidity moisture. The Copper metal reacts with Oxygen, resulting in the formation of an outer layer of Copper Oxide. This reaction on Silver results in tarnishing and taking on a blackened appearance.
 
So, what are the common causes ? Moisture and humidity, cosmetics and sunscreen, perfumes and sprays contain chemicals.
 
In conclusion any silver can turn black when it encounters a silver-sulfur salt-forming environment.
 
How to preserve silver jewelry? 
 
You know, silver jewelry usually gets dull because silver itself has the characteristic of absorbing sweat (this is also its antiseptic ability). Therefore, after a while, your silver rings, bracelets or necklaces will no longer shine. No problem! You can easily polish it up! Shimmer offers you the two following methods:
 
Method 1: You can use soda, such as Schweppes. Pour the soda into a small cup, then soak your jewel in it for around one minute. After that, take it out, wash again by tap water and dry it by paper towel. Done! So easy!
 
 
Method 2: You can use toothpaste. Apply a little toothpaste, add water, and then polish your jewel using a soft brush. Remember to do it softly to avoid scratches. This is also a fast and easy way.
 
 
Method 3: Use  silver polishing cloth - which you can find at any silver jewelry store. Just a light wipe to remove the dull layer of silver then our jewelry will be as shiny as new.
Lastly, please make sure your silver jewels have no contact with perfume, salt, hair dye, soap and tofu. Also, please store them neatly to avoid breakages and misshapes.

 

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