I have several cz's and to be honest i am not impressed with ziamond's cz at all.  plus their service is awful and the people are rude. if you have a problem with your order forget it!  or if they made a mistake, like in my case, it will take weeks to get resolved.   the only thing nice about ziamond is their website which makes them look like they have the best cz's and they really don't.  the ones from qvc are better than theirs.  the ring i bought from ziamond i ended up selling on ebay.  plus if you do your research you'll find the same designs somewhere else for a fraction of the price and the cz's will be better.  hope this helps!