What is the difference between Moissanite and Cubic Zirconia?
This question we hear often. It is true that both moissanite and cubic zirconia are imitation diamonds which are man made. Other than this, the difference between these stones far outweighs their similarities.
First, we should discuss the difference in the make-up or the composition of each stone. Moissanite is silicon carbide, a compound with chemical formula SiC. On the other hand, cubic zirconia is zirconium dioxide, ZrO2. Moissanite is composed out of silicon and carbon, whereas CZ in its crystal lattice contains zirconium and oxygen. Diamond is pure carbon. If you compare both of them to diamond, moissanite comes much closer.
Which stone is brighter or has more fire and ice? Due to the structure of a moissanite stone it is naturally doubly refractive, which increases the amount of light dispersion from the stone, making it a brighter stone then both the diamond and a cubic zirconia.
The color of the stones is significantly different. Cubic zirconia is a perfect, flawless and pure white stone. This is another clear way to distinguish the difference between CZ and moissanite. Due to the complicated process of production, moissanite stones are neither perfectly white and transparent, nor flawless. They often possess slight greenish or even yellowish hues, along with some imperfections in the structure. For this very reason, moissanite stones are that much closer to a genuine diamond vs. a cubic zirconia.
What is the difference in the stone’s durability or hardness? Even though all three stones, moissanite, diamonds, and cubic zirconia, are relatively hard, that does not mean they are unbreakable. The hardest and most durable is of course the diamond with the maximum possible hardness of 10 on the corresponding scale. Moissanite is dangerously close with 9.2, and the least hard of them is CZ with 8-8.5.
Finally, there is a significant difference in the cost between these stones. As you know, cubic zirconia costs significantly less than both moissanite and diamonds. If you are looking for beautiful jewelry but want to stay in budget both the CZ and a moissanite may be a better option over a diamond. The 5A rated cubic zirconia (highest quality) costs approximately $100 per carat. A moissanite stone is approximately 10% of the cost of an equivalent diamond of the same carat weight. Moissanite stones have maintained their value over the past 20 years and would most likely make a better investment over a cubic zirconia. 
My Faux Diamond 