Any diamond important to you should be examined and bought loose or unmounted. Once the diamond is set into a ring or other jewelry piece, it can be difficult if not impossible to see certain characteristics and differences in the diamond. Also keep on the lookout for diamond prices that are "just too good to be true". They usually are - it is hard to find a real bargain.

Here are some methods used to deceive buyers of diamonds:

Weight misrepresentation. If a jewelry piece has more than one diamond, the total carat weight (TW) will be given. However, the weight of the individual diamonds should also be given, particularly if there is one main diamond. There is a huge price difference between one diamond weighing 2 carats and several smaller diamonds weighing 2 carats total.

Also, always look for carate weight (CT), not carat spread. Carat spread indicates how large a diamond appears to look, not how much it actually weighs.

Color alteration. Diamonds can be artificially treated to improve their color (making brown diamonds look more colorless) or making colored diamonds more intense in color. The different methods used to alter color include radiation, heating, applying coatings, and the high pressure high temperature (HPHT) treatment. Bellataire diamonds for example are diamonds that have undergone a patented form of HPHT treatment.

All diamonds that have undergone any kind of color treatment should be clearly listed as "treated" on a diamond grading report.

Flaw concealment. Flaws, or inclusions, in diamonds may be concealed by the jewelry mounting. In addition, flaws can be removed or made more invisible by filling in fractures with a diamond or by laser drilling. Again, any such treatment should be clearly marked as such on the diamond certificate.

Certificate alteration or forgery. Sometimes information, such as color grade, clarity (flaw) grade, cut grade, or other information is deliberately misrepresented on a diamond certificate. Make sure the information on any certificate is accurate by taking the diamond to an independent gem testing laboratory for grading.

Diamond switching. Sometimes a diamond is switched out and isn't the one listed on the diamond certificate or report. This can happen anytime the diamond is sent out for service. Use Gemprint to take a "fingerprint" of the diamond to prevent this from occuring.

Diamond imposters. Make sure the diamond you are buying is actually a natural diamond and not an imitation diamond. Common diamonds imitations include moissanite, cubic zirconia (CZ), quartz, and even glass. There are various tests available that can detect these imitations or simulants.