The diamond is unsurpassed in the hierarchy of gems. Its elegance has been revered since its discovery.

As a purchaser of diamonds for engagement rings, whether past, present or future, one may wonder why there is such variation in price from store to store. What characteristics constitute a $5,000 diamond versus one that costs only $500? 

The grading system for diamonds is based upon four different elements. Firstly, size will play a large role in the price. This is referred to as the “carat weight,” and it is determined on a 100 point scale. The larger the carat weight, the higher the value.

Carat size may push the price up, but only slightly if there is no clarity. Several facets determine clarity on both an internal and external basis. Internal aspects, dubbed inclusions, and external aspects, dubbed blemishes, all contribute to the overall clarity score.

The number of inclusions as well as their size and tint all factor into the overall clarity score, as do the number and size of surface blemishes. A flawless diamond is at the top end of the clarity scale, referred to as ‘pure’. An inexpensive diamond may carry with it the classification of ‘heavily included’.

The appearance or absence of these imperfections is a result of how the diamond was formed underground over thousands of years. Since diamonds are often thought of as the symbol of perfection in our society, the more perfect they actually are under the scrutiny of a microscope, the more expensive they become.

Color is the next factor that determines a diamond’s overall value. If possible, a diamond should be as clear as water, but this is not always the case. Colors from other gases and minerals around during the time of the diamond’s formation may have altered its clean appearance and left the gem tinted.

Diamonds range in color from a designation of “D” to “Z”, with “D” being no color at all, and “Z” being a diamond with a color that is deep enough to be very noticeable to the human eye.

Lastly we need to understand the effect of the cut on pricing. The quality of the cut may not be as easy to evaluate for an inexperienced buyer as some of the other factors, but it is nevertheless a critical element as it gives the diamond its sparkle.

To view a diamond from the point of view of the cut is to investigate whether or not it has any ‘fire’. Like the other criteria for grading, the cut has it’s own grading scale that goes from excellent to irregular. If the diamond doesn’t knock your socks off then it likely has not been cut very well.

So there you have it, the 4 C’s of choosing a diamond: carat, clarity, color and cut. Understanding these basic concepts before you enter a diamond store will go a long way towards making an excellent purchase decision.

By Brad Morgan: Some of the most impressive diamonds are referred to as colored diamonds. Find out how manufactured diamonds have an impressive quality in their own right.