Introduction to the 4 C's
Among diamond purchases, the most common reason is for wedding engagement. Choosing the diamond for your engagement could be the single-most emotionally charged purchase you will make in a lifetime, even more than a home! It is important that you understand what you are buying, to further enhance the experience. You have probably already heard of the 4-C's; Cut, Color, Clarity, and Carat Weight are factors that will help you to make an intelligent choice with confidence.
Cut not only refers to the shape of the diamond, but also to the size, angle, uniformity and polish of the facets.
Color is sometimes "graded" on a scale. However, scales are not uniform: a "D" may be the best color for one scale, but not for another. Make sure you know how a particular scale and grade represents the color of the diamond you're considering.
Clarity refers to the presence or absence of internal flaws, called inclusions, that occur naturally within the stone, or to external blemishes, such as scratches or chips. A diamond can be described as "flawless" only if it has no visible surface cracks or other imperfections when viewed under 10-power magnification by a skilled diamond grader.
Carat weight may be described in decimal or fractional parts of a carat.
Given a specific budget, you can either get a smaller diamond with better & rarer qualities, or get a bigger diamond with lesser qualities. As a rule of thumb, having a balance of the 4 C's is better than going extreme on one C, but it ultimately depends on your personal preferences... or the hints from your fiancée.
Before we proceed any further, we should note that the tips given here, or from any other source that you might obtain, will be invaluable knowledge to guide you with the buying process. However, there are always bad apples in the diamond industry and these scammers would have years of experience in diamond merchandising and scamming. Therefore, always apply common sense too, before laying down the dough : Buy from a reputable store. And, if it's too good to be true, it probably is.