Cz (cubic zirconia).

Details Brilliant-cut cubic zirconia, 5mm diameter (measures about 30 points on a diamond gauge). As an expert, YOU can probably tell Cz from diamond at a glance. But to your customers, Cz will look identical to diamond. And your customer will be impressed when you show them how easily you can distinguish between the two with your diamond tester. Why? Q. This item is discontinued.  Why? A. Because this is not something we sell (we don't sell gemstones); we just happened to 'come across' some these, we give them away some of the (more expensive) diamond testers - but you can buy some if you wish.