Buying Loose Diamonds
Purchasing loose diamonds can be an investment for the future, so it’s best to choose diamonds that will hold their value in the long term. Although you may not be concerned about the resale value of your diamond at the time of purchase, you may be interested in selling your diamond or trading it in for an upgrade later. When buying a diamond, it is best to know what contributes to its quality and value to ensure that you make a sound purchase. An important factor to consider is whether to buy a natural diamond or a treated or enhanced diamond.
Made from carbon, diamonds are the hardest known substance to man and are both a naturally occurring and manufactured abrasive. Natural diamonds form at high pressure high temperature conditions existing between 85 to 125 miles in the earth’s mantle. It takes a diamond 1 to 3 billion years to form beneath the earth. Once formed, a diamond travels to the earth’s surface via streams of molten rock. Throughout this process, natural diamonds acquire inclusions and or flaws within them that give them their own unique “fingerprint”.
Diamonds can be purchased in various sizes (carats), shapes, colors, and clarities. Natural diamonds are preferred over enhanced or treated diamonds because of their rarity and individual fingerprint. No two natural diamonds in the world are identical; each one is unique whether it’s because of its color or clarity or both combined.
Enhanced or Treated Diamonds
The term “enhanced” may sound like a positive feature, however, any diamond that has been enhanced has been treated and altered from its natural condition to artificially improve its appearance. If you decide to purchase an “enhanced” diamond, find out what kind of treatments have been used and how they might affect the value of the diamond. You should also be concerned with the long term care and appearance these enhancement treatments may have on the diamond, as enhancements sometimes result in discoloration or cracks in the diamond.
Enhanced diamonds, unlike high quality natural diamonds are natural diamonds that have had very specific treatments done to them to improve their characteristics, or their natural “flaws”. One type of treatment is laser drilling, which is a process that removes minor inclusions in a diamond to produce a clarity enhanced diamond. This process will typically create lines that resemble tiny trails, which are visible under side-view magnification. The laser may dissipate the imperfection, or chemicals may be injected into the resulting tunnel to bleach away the color. This is a more permanent process than fracture filling. However, it is highly debated whether or not this process damages the integrity of the diamonds, thereby decreasing the value of clarity enhanced diamonds in the long term.
Fracture filling is a treatment that adds a glass-like resin material to a natural diamond to close small cracks. Since the filling has the same optical illusion and refraction index as a natural diamond, it’s nearly impossible to detect the “repair” to the flaws. Fracture filling is not a permanent treatment as heat from future repairs, cleanings, and even sunlight can erode the filler or possibly darken its color, making the diamond less valuable as time goes on.
One other type of enhancement treatment is called HPHT (high-pressure high-temperature). HPHT is a treatment process that General Electric developed to permanently change the color of a diamond. First used to turn yellowish diamonds into “fancy” colored diamonds, this process is commonly used to turn yellow or brown diamonds into colorless diamonds to be sold at a significantly higher prices. HPHT involves putting a diamond into a pressure chamber and squeezing it at high pressure and high temperature for a short amount of time. Although some feel that this treatment should be considered a standard technique and claim that this process is just finishing the job that nature started, the Federal Trade Commission feels that it is an artificial process and requires that HPHT be disclosed. When HPHT treatment is detected in a diamond, the Gemological Institute of American (GIA) notes it on their reports as “HPHT Annealed” or “Artificially Irradiated” and insists that such diamonds be laser-inscribed with the same designation. A diamond that has been enhanced by GE will be inscribed with the symbol “GE POL”.
Detecting Enhanced or Treated Diamonds
There are different ways to detect if a diamond has had clarity enhancement treatments done to it. As mentioned above, laser drilling results in very thin, white lines or tunnels within the diamond that do not follow the pattern of the loose diamond. When fracture filling is used, the diamond may appear flawless when viewed from the top, but careful examination from the sides or other angles may reveal flashes of color that disrupt the pattern of facets in the diamond. Fracture filled diamonds may also have air bubbles trapped within them. Because these hints are only visible from the sides, it is very important to examine the diamond closely and preferable as a loose diamond rather than set into a diamond ring setting.
The Controversy About Enhanced or Treated Diamonds
Due to the controversial nature of diamond treatments within the industry, the CIBJO (World Jewelry Confederation), the United Stated Federal Trade Commission, and the GIA all require the disclosure of all diamond treatments at the time of sale. Without this disclosure, consumer confidence in diamond purchasing would be significantly damaged.