Ring is not silver

In december 2014 me and my fiance' went to Ilanga mall's Branch to purchase a wedding ring for our wedding on 14 february 2015, as do all woman I took my time on deciding which ring to take and then I decided on a 3band silver ring, i repeatedly asked the sales lady if it is real silver, due to the fact that I cannot by any means wear **** jewelery, like brass or bronze or anything like that, and she assured me that it's real silver. So my fiance' then bought the ring. So we stowed away the ring in a safe, so that it would not be harmed or anything. Then on our wedding the 14th of February 2015, we exchanged our vows, and as do normal he put on my wedding band. So the wedding went on and the whole night my hand was itching. So the next day whilst cleaning up the venue, i took my wedding ring off, and there it was, under the ring there was blue, asif engraved in my skin. I instantly knew that the ring was not real silver. So I would like to place a formal complaint against this company, this ring was suppose to be a happy memory of my wedding day and the only thing I have is a almost black ring that makes my finger turn blue.