We know that a diamond may be one of the biggest and most important purchases that you will make in your lifetime. As with any significant purchase, we recognize the importance of understanding exactly what you are buying. The characteristics and features diamonds can be confusing, so we hope that the following guide will help you make a well informed decision and help you with your purchase.

Diamond Jewelry - Celtic Promise Every diamond at Celtic Promise is individually selected by our Master Jewelers to meet our strict criteria for quality and value. While we offer diamonds up to half a carat in size, if you’re looking for something larger we will be happy to source it for you so please do not hesitate to Contact Us.


Cut, color, clarity, and carat are the "4Cs" that guide a jeweler in determining a diamond’s quality and value. The 4C’s are used throughout the world to classify the rarity of each diamond.

"Clarity" refers to a diamond’s freedom from internal inclusions or imperfections such as fractures or tiny crystals within a diamond. A diamond is considered flawless only when a trained eye can detect no imperfections under 10-power magnification. An inclusion can be a tiny crack, a piece of mineral or any other imperfection that contributes to the unique makeup of a diamond. Practically all diamonds have inclusions, which are created during the formation of the diamond in the earth. Only the rarest of diamonds are free of imperfections and considered flawless.

"Cut" refers to the angles and proportions of a diamond, and it determines its brilliance. A well cut diamond with good symmetry will insure that light is reflected to its maximum potential, making it glitter and sparkle. Poorly cut diamonds have dulled brilliance. Many gemologists consider cut the most important element of the 4C’s. The cut of a diamond also refers to its anatomy, symmetry, and specific dimension measurements.

"Color" refers to how colorless a diamond is. The less color a diamond possesses the better the color grade. Acting like a prism, a diamond with little color will produce excellent sparkle and fire when light reflects through it. Diamonds are found in almost every color, but white-colored diamonds remain most popular throughout the world today.

"Carat" refers to the weight of a diamond. Larger diamonds are found less frequently in nature and are therefore more valuable. For this reason a 1 - carat diamond will be well over double the price of a ½ -carat diamond, assuming clarity, cut and color are equal. One carat is equivalent to 200 milligrams.

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Diamond Jewelry - Celtic Promise A diamond that is originally taken from a mine is very different to the finished product that we find for sale on the retail market. The original form of the stone will dictate what final shape that the diamond takes. A master cutter will carefully analyze a raw diamond and determine which shape will optimize the stones individual characteristics. Expert cutters will make the decision based on maximizing the size of the stone and illuminating inclusions contained within it.

Diamonds come in seven different shapes: round, oval, heart, emerald, marquise, pear and princess. However, round diamonds continue to be the most popular throughout the world today. While diamonds come in every color of the rainbow, white has always been the most popular choice for buyers. Red diamonds are the rarest of all.

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To ensure valued and educated purchases with all of our diamonds, Celtic Promise adheres to the strict rules and regulations as set out by the G.I.A., Gemological Institute of America and the E.G.L, European Gemological Laboratory, who use a strict system of regulations and standards to classify diamonds. Please Contact Us if you require additional information, or specific certification for any of your diamond jewelry purchases.

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