For starters be sure to look for the presence of hallmarks and fineness of the metal. This is a simple feature, but it does not give a 100% guarantee of authenticity. The mark can easily be forged. But each jewelry the presence of this stigma should be mandatory.
Silver is too heat-conducting metal, that is, if you push the product in hand or immerse in boiling water, it instantly becomes the same temperature.
With sulfuric ointment. If you smear the product sulfuric ointment, which is sold freely in pharmacies, and will leave in a few hours, the silver jewelry this place, on which lay the ointment should be black.
You can also use iodine, chalk, special reagent "test silver", reaction to which will be a similar reaction to the sulphur ointment.
Scratch the silver thing in the hand if the palm remains blank, it speaks about the quality of the metal. And if the hands are dirty, it is likely that silver diluted with zinc.
The presence of silver deposition can be checked using a conventional needle. If you scratch the product the needle, slide coating, exposing the metal. Usually use brass, which has a reddish color.