In nature, diamonds are created at extremely high temperatures and pressures in the mantel of the Earth, at a depth of around 140 to 190 kilometers. Trace amounts of boron will create a blue diamond, while trace amounts of nitrogen can create a naturally yellow diamond, and exposure to natural radiation can create green diamonds.
In the laboratory, processes which would usually take thousands of years can happen in a mere few hours. The processes usually used today are irradiation and annealment; and HPHT.
The most common process used for color enhancing a diamond consists of two steps : Irradiation and Annealment. A third process, High Pressure High Temperature (HPHT) is often used to produce pink diamonds. These processes enable a nearly colorless diamond to obtain a beautiful variety of colors.
Natural color in a diamond comes from the presence of trace impurities in the stone or structural irregularities at its atomic level. The reason a diamond looks the way it does is all down to the way its atoms are arranged. Irradiation activates the diamond’s color center – a network of atoms and subatomic particles that work in a way that gives each diamond a particular color. Irradiation promotes changes in the stone’s atomic structure in the laboratory – with the same result: the diamond gains color. Irradiation doesn’t actually ‘give’ a diamond color, therefore, but rather simply unlocks its color potential.
Irradiation - Currently the safest way to irradiate diamonds is by using a machine known as a linear accelerator. This fires a pulsed beam of electrons at the diamond, which then disturbs the electrons of the diamond itself, causing them to be knocked loose and ‘captured’ by other atoms. The light absorbing structure of the gem is changed and, as a result, so is their color. This process is known as low energy electron bombardment.
Annealment - Exposure to electrons gives diamonds a greenish blue or blue colors. In order to get the whole multitude of colors, irradiation is followed by heating to an extreme temperature of around 450 C/850 F and upwards. We call this ‘annealment’ as it is done in an oxygen-free environment. This causes the stones’ atomic structure to rearrange yet again, resulting in a range of new colors. Annealment is a process that mimics nature, since natural heating in the right environment can alter a diamond’s color as well.
The High Pressure, High Temperature (HPHT) process is designed to precisely mimic the natural conditions in the mantel of the Earth where diamonds are created. The process allows the natural trace elements within a diamond to relax and to display their natural color. Highly sophisticated machines expose the diamonds to heightened heat and pressure resulting in the change of the color of the diamond. When it emerges from the machine, the diamond is initially covered in a frosty outer layer. After polishing, their newly attained beauty is revealed. Only diamonds of very high clarity can be used for this process, as any small feathers in the diamond will result in worsening or even chipping out of the diamond during the HPHT process.
Enhanced pink diamonds are the most expensive because they are the hardest to produce. True pink is not a color which emerges easily in diamonds during irradiation or HPHT. Scientists are currently unsure of which element creates pink diamonds. For a thousand carats of other colors, only 2-3 carats emerge as purple or pink, and of that the large majority are on the purplish side. For this reason, the diamonds with the least amount of purplish undertones are more expensive.
Generally during the processes of irradiation and HPHT (high pressure, high temperature) the diamonds which emerge will be on a scale from purple to pink, with the more pinkish colors being the most expensive.
Pink diamonds are priced according to the four C’s. The larger, the better quality the cut and the clearer the diamond, the more expensive it will be. When it comes to the color, pink diamonds have a premium placed over purples because they are so difficult to create.
Pink diamonds are the rarest on Earth. A pink diamond therefore comes with an extra level of desirability that the white diamond simply cannot match. Many celebrities (including David and Victoria Beckham) have recently been spotted wearing pink diamonds, and the most fashionable of jewelry buyers will already know that color diamonds are currently very in vogue.
At Spirit Lake Silver and Gold, we can provide the pink diamond you desire that will fit your budget. Shop with us today to find your the pink you are dreaming of!
- February 08, 2019
- Amy Thiessen