diamonds and synthetic diamonds difference

Crystal habit
Synthetic diamonds often: cube, octahedron, and both poly shape
Natural diamonds often: octahedron, rhombic dodecahedron, and both poly shape, as well as common triangular flakes twins
Color
Synthetic diamonds often core drills  brown, and is often irradiated to change color into blue, orange, pink, brown and golden yellow
98% of natural diamonds are colorless - yellow series.
Surface and internal texture
Synthetic Diamonds: You can display or cross-shaped dendritic texture
Natural Diamond: The surface dents or Triangle Triangle common, often show the internal structure associated with the texture.
Magnification
Synthetic Diamonds: seed and phantom zone, various forms of metal inclusions
Natural Diamonds: no metal inclusions
Visible absorption spectrum
Synthetic diamond: None 415.5nm absorption lines obtained in liquid nitrogen under low temperature conditions can be measured less than 500nm 658nm absorption and total absorption peak
Natural diamonds: mostly 415.5nm absorption lines
UV fluorescence
Synthetic Diamonds: usually no cbn grinding wheel  fluorescence under long-wave, and shortwave under yellow-green, orange and yellow fluorescent, the "Maltese Cross zoning" phenomenon, while there are obvious phosphorescence
Natural diamonds: mostly under long wave blue and white fluorescent, weak or displaying inert under shortwave.
Cathodoluminescence instrument
Synthetic Diamonds: UV fluorescence distribution with similar characteristics, different growing areas show different fluorescence band
Natural diamonds: mostly irregular
Because natural diamond growth when the environment is changing at all times, however, the growth of synthetic diamond environment is static.
IR
Synthetic Diamonds: 1130 Cape beam absorption band
Natural diamonds: 1176,1282 beam absorption bands.
Conductivity
Synthetic Diamonds: some may have  diamond blade circular saw conductivity or thermal conductivity
Natural Diamond: In addition to Blue Diamond is a semiconductor outside, are not conductive, and is not magnetic.
Other
Such as exception birefringence