It's essentially cubic zirconia which is hardwearing and very sparkly, and surprisingly similar in composition to a diamond. I think the problem is that the stones tend to be cut large, rendering them less "believable." The Jewellery Channel do many cubic zirconia designs. They call it "Swarovsky Zirconia" but it's all much of a muchness. I think you're better off with QVC as although TJC offer a 30 day MBG, they do this really annoying falling price thing where they hyperinflate the price and make a whole load of noise about how they are bringing the price down again. They keep saying "we won't charge you this" and "we won't charge you that" and I'm sitting there thinking "ffs how ****ing much ARE you gonna charge me?" TJC always try to give the impression that they are being a bit naughty and that if the Management were watching they would be foaming at the mouth at the low prices. In truth, the management SET the prices. It's all overseen by a stony-faced little Indian man called Amit Aghrewal. I don't know how they get away with all their charades, although I do like some of the presenters, particularly Derek Marks who I find quite entertaining. There's another one called Chloe who tries to be all posh! There's another called Stacey who has a really annoying voice! Derek me a bit of Paul Lavers! QVC is better I think.At least they don't fuss about the price too much.