Silver jewellery, and particularly silver rings which are worn often are unfortunately are prone to tarnish.
Sterling silver is a mixed metal, combining pure silver (92.5%) and copper (7.5%) and it is the copper in the silver that reacts with moisture, and sulphur in the air to create the tarnish. As such the tarnish is produced more quickly in areas with high humidity - like swimming pools.
The tarnish will also happen with different speeds on different people, due to the differing body chemistry and the environments they live in.
I did a blog post a while ago on the basics of how to keep your silver shiny.. and have since found lots of other useful info on the internet about it.
I thought this post was particularly informative on how to clean and care for sterling silver jewellery and covers everything you could possibly wish to know.
There are a lot of other websites which suggest using aluminium foil, and bicarbinate of soda - but I must admit I've not tried it yet. I'm also lucky as I got myself a super dooper ultrasonic cleaner for my workshop, which keeps all my silver nice and shiny, (and you're always welcome to get in touch about sending your jewellery for a go in it!) but I'd love to hear any of your other tips and tricks if you've got any.
To stop the tarnish building up in the first place there are lots of suggestions like not wearing your rings in the shower, or pool, or when you're cleaning etc..
Pah - I don't know about you, but I can't be doing with taking my jewellery on and off all the time.
Apart from anything else I'd forget to put it back on again.
I personally reckon the easiest solution is to keep the tarnish at bay by getting a silver polishing cloth, and giving them a quick rub every day just before you put them on. By keeping the tarnish down in that way, it should never build up to a problem level.