A lab created diamond is a real diamond. That's the part people are often surprised to hear. It's not a simulant like cubic zirconia or moissanite — it's made of the exact same material as a mined diamond: pure crystallized carbon. The only real difference is where it comes from. Instead of forming over billions of years deep in the Earth's mantle, a lab grown diamond is grown inside a controlled facility over the course of a few weeks.