Why silver will darken from the point of view of chemistry?
Silver chain – this piece of jewelry, which is composed of other metals, e.g. copper, which under the influence of moisture oxidizes and darkens. The lower the sample of the product, the greater and faster it will darken. And the silver in the interaction with sulfur forms a sulfite, which is black. Silver will always be dark, because skin contact with comes in contact with salt then, which is essentially pure sulfide. The chest area where you would normally wear chain, fitted with active sebaceous and sweat glands, so this place is the decoration quickly darkens.
If you don't sweat heavily, but the chain is still darkened, then the problem may be the use of cosmetics, which are composed of components that contribute to the blackening of silver.
Perhaps you live in a region where the soil contains large amounts of hydrogen sulfide. In the area of silver jewelry to darken.
Can darkened chain to be a sign of the presence of the disease?
If the chain is dark, then this is another reason to undergo a medical examination. Silver can change color for kidney disease. Moreover, in certain diseases it may not darken and lighten, which indicates that the sweat came nitrogenous substances.
Any disease which is accompanied by increased body temperature, is the cause of darkening of silver. This is because the sweat and sebaceous glands begin to work very hard. The same happens when a person is nervous, worried.
Pregnant women say that their chains darken instantly. This is due to hormonal changes in the body, which affects the excretory system. Silver may darken in the background of medication containing sulfur or hormonal substances.
Why silver will darken from the point of view of mysticism?
People say that if a chain or cross darkened, the man was an evil eye or a spell. Psychics believe that the darkening of silver attests to the astral human rights violations.
There is an opinion that silver is a powerful amulet. Therefore, when the silver product of sharply acquires a black color, it is believed that in this way silver took a stream of negativity.
All of this has no scientific explanation and evidence, but people tend to trust in the unexplainable.
In any case, if your chain is darkened, do not worry – there are many ways how to return it to its original shiny look.