Most jewellery of that value is covered by the Authenticity Guarantee.
Items by that brand over £500 are certainly covered.
Did you buy from an overseas seller?
Personally, I would not buy an item of that value online - if I had that much to spend, I would want to see and touch the item first.
However, it's worth remembering that Ebay only cover items for 30 days (not 2 months) and, if you do spend that kind of money, it's a good idea to get a reputable jeweller to check it out soon after you receive it.
"There are two ways to be fooled. One is to believe what isn't true; the other is to refuse to believe what is true.”
Søren Kierkegaard, Danish philosopher (1813 - 1855)
