According to the June 15, 1984 issue of the Wall Street Journal, CZ's have more light dispersion(fire) than diamonds and almost the same reflective index(brillance). This is shown as follows:
| Dispersion (fire) |
Reflective index (brillance) |
Hardness | Specific Gravity |
|
| RoStar SD | .060 | 2.15 | 8.5 | 5.95 |
| Diamonds | .044 | 2.42 | 10.0 | 3.52 |
