This information, in conjunction with our article on distinguishing diamonds, can help you separate diamonds from their imitators.
Identifying Synthetic Diamonds
Until relatively recently, gem-grade synthetic diamonds rarely appeared in jewelry. This is changing. Consult our article on identifying synthetic diamonds for advice on distinguishing natural or mined diamonds from their lab-created counterparts.
Properties of Natural Diamonds vs. Diamond Simulants
|Properties||Natural Diamond Type Ia||Natural Diamond Type Ib||Natural Diamond Type IIa||Natural Diamond Type IIb||Moissanite||Cubic Zirconia|
|RI||2.417||2.417||2.417||2.417||2.648 – 2.691||2.15 – 2.18|
|Dispersion||.044||.044||.044||.044||.009 – .104||.058 – .066|
|Optic Character||Isotropic||Isotropic||Isotropic||Isotropic||Uniaxial +||Isotropic|
|SG||3.515||3.515||3.515||3.515||3.17 – 3.22||5.56 – 6.00|
|Hardness||10||10||10||10||9 ¼||8 – 8 ½|
|Cleavage||Perfect, four directions||Perfect, four directions||Perfect, four directions||Perfect, four directions||None||None|
|Absorption Spectra||Dark line at 415 and 478 nm, often more||Increasing absorption towards blue end||Variable, usually 504||Variable||No sharp|