human
How can I tell the difference between a real diamond and a cubic zirconia?
assistant
Real diamonds are made of carbon, while cubic zirconia is a synthetic gemstone. Diamonds have a hardness of 10 on the Moh's scale, while cubic zirconia has a hardness of 7.5. So if you want to know if it's a real diamond or cubic zirconia, look at the hardness number. If it's harder than a diamond, then it's likely cubic zirconia.