1, color:
Synthetic diamonds are often tan, and are often irradiated by blue, orange, pink, brown, and golden yellow.
98% of natural diamonds are colorless-light yellow series.
2, crystal habits:
Synthetic diamonds are often: cubes, octahedrons, and both
Natural diamonds are usually octahedrons, rhombic dodecahedrons, and polycondensation of both, as well as common triangular thin-film double crystals.
3, zoom observation:
Synthetic diamond: seed crystal and its phantom area, various forms of metal inclusions
Natural diamond: no metal inclusions
4, surface and internal texture:
Synthetic diamond: can display dendritic or cross-like texture
Natural diamond: The surface of a common triangle dent or triangle, the interior often shows texture related to the structure.
5, UV fluorescence:
Synthetic diamond Synthetic diamond: Under long wave, it is usually not fluorescent. Under short wave, it has yellow-green, orange-yellow fluorescence, there is "Maltese cross zoning" phenomenon, and there is obvious phosphorescence.
Natural diamond: It is mostly blue-white fluorescence under long wave, weak under short wave or inert.
6, visible light absorption spectrum:
Synthetic diamond: Without 415.5nm absorption line, the absorption peak at 658nm and full absorption below 500nm can be measured under low temperature conditions obtained by liquid nitrogen.
Natural diamond: Most of them are 415.5nm absorption lines
7, UV fluorescence:
Synthetic diamond: It is usually not fluorescent under long wave, yellow-green, orange-yellow fluorescence under short wave, “Maltese cross zoning” phenomenon, and obvious phosphorescence
Natural diamond: It is mostly blue-white fluorescence under long wave, weak under short wave or inert.
8. Cathodometer:
Synthetic diamond: similar to the distribution characteristics of ultraviolet fluorescence, different growth areas show different fluorescence bands
Natural diamonds: Mostly irregular Because the natural diamond grows, the environment changes from time to time, but the synthetic diamond growth environment is always the same.
9, infrared spectroscopy:
Synthetic Diamond: Absorption of 1130 beam
Natural Diamond: Absorption Bands of 1176, 1282 Beams