Treated Diamonds
Diamonds that formed naturally inside the Earth’s surface that went through processes to improve its appearance.
Synthetic Diamond
A diamond made by humans in a laboratory using the same composition, structure and characteristics as an Earth born diamond.
Diamond Simulant or Imitation
A diamond look-a-like. Not a diamond at all but only resembles a diamond.
Clarity Treatments:
Laser Drilling
Eliminates or lightens included crystals by burning a channel to reach the inclusion then an acid is injected down the channel to dissolve or bleach the included crystal. This will add another characteristic (laser channel) but will improve the diamonds overall appearance.
Fracture Filling
The process of filling fractures and cleavages with a glass-like material that mimics a diamonds transparency, color and optical properties. This process can only be done within a vacuum so the glass will completely displace the air inside the fracture.
The clarity treatments will give the illusion of an improvement in two clarity grades, but the characteristics are still there and the true quality stays the same or worsens because of the added laser channels. Laser drilling and fracture filling are an ethical practice AS LONG AS the practice is disclosed to the customer. If they are not disclosed to the customer then it is regarded as blatantly fraudulent.
How to detect fracture filled diamonds:The first and foremost step is to look for the “flash effect”. The flash effect is caused when light reflects from the boundary between the filling and the diamond and looks like a long (or short) channel of concentrated color. The flash effect could be blue and orange or purple and green in color.
Color Treatments:
Coating
When a diamond (usually girdle or pavilion) is covered with a thin layer of colored plastic or chemicals to give an illusion, no matter how slight, of less color. Coating also can change the diamond to a fancier colored diamond or to a darker shade of a fancy color. No matter how much coating that is on the diamond, it is considered a deceptive practice.
Irradiation or Annealing
Is the process of submitting a fancy-faint colored diamond to high heat to enhance its color creating a darker or deeper colored diamond.
High-Pressure-High-Temperature (HPHT)
Is the process of altering a diamond at the molecular level. This removes some, or all of the brown color out of a diamond, and in some cases can change a brown diamond into an intense yellow or green diamond.
One company is famous for the HPHT process and its name is General Electric. These diamonds have only a limited market. The main distributor is Pegasus Overseas Limited (POL for short) and marketed under the following names: GE POL, Pegasus or Bellataire. The diamonds are laser inscribed on the girdle of every diamond they sell.
Irradiation, Annealing and HPHT treatments are considered ethical as long as the process is disclosed to the customer. Coating is a deceptive practice even if it is disclosed.
How To Detect Treatment, Synthetic, or Simulated Diamonds:
Synthetic Diamonds often have internal characteristics, color zoning and fluorescence that differ from natural diamonds. Synthetic Moissanite, like mentioned above, has a doubling effect.
Fancy colored diamonds can only be positively distinguished from color-treated diamonds in a laboratory of gemologists using their advanced instruments. The only real fancy diamond that will have a hard time being distinguished is the green diamond. The green diamond was, or could have been exposed to heat, pressure and irradiation naturally.