How to tell if a diamond is good quality

Jessop's knows diamonds. You won't find a more exceptional team of diamond experts in any jewelry store in San Diego. Take advantage of our expertise. Please visit us for a diamond lesson in our San Diego jewelry store.

Jessop's of San Diego is a member of the American Gem Society, the internationally respected organization dedicated to proven ethics and consumer protection. Jessop's staff members have achieved the coveted titles of American Gem Society-certified gemologist and American Gem Society-certified gemologist appraisers. These titles are conferred only on those who have completed advanced training, passed an examination and reached what the American Gem Society considers the highest level of achievement and knowledge in diamonds and fine jewelry.

Many Jessop's staff are graduates of the Gemological Institute of America, the most respected source in the world for diamond grading. Jessop's features the finest quality of any San Diego diamond store. We know you will find that our San Diego jewelry store offers unique and stunning diamond jewelry for all occasions.

Diamond Grading

Every Jessop's diamond is graded to the three highest standards in the world - Jessop's integrity, the Gemological Institute of America (GIA) and the American Gem Society. The GIA set the standards for diamond grading many years ago. Within the jewelry industry, GIA and American Gem Society grading reports are recognized as the most accurate. As your diamond source in San Diego, we adhere strictly to these standards. Jessop's San Diego diamond store uses only these two certificates for reliability.

We employ only skilled, certified diamond graders who conduct the grading in our American Gem Society-accredited diamond lab. This diamond grading is conducted on site in our San Diego jewelry store. From diamond engagement rings to wedding rings we are San Diego's source for diamonds. Most of our diamonds also have secondary American Gem Society and GIA lab-grading reports.

The American Gem Society recently created a new diamond-grading document. This grading report, called the Light Performance Evaluation, is unique. It is a sophisticated analysis of the brilliance and dispersion, or fire, of an individual diamond resulting in a grade for light return. Jessop's finest diamonds excel in brilliance, backed by the Light Performance Evaluation. To see this for yourself, please come in and visit our San Diego diamond store.

As more people have requested diamond-grading reports, more jewelers have obliged with official-looking grading reports. Pay close attention to the lab names or initials on those reports. Only lab reports that carry the initials GIA and the name American Gem Society are the real thing. That's exactly what you will find on every Jessop's diamond-grading report - another reason Jessop's is the diamond source in San Diego.

Jessop's diamonds are the diamonds you'll be proud to give and to own. Jessop's diamonds are the diamonds for peace of mind. Jessop's diamonds are considered among the finest diamonds in San Diego and we are proud to offer diamonds for all occasions. Wedding rings, diamond engagement rings and custom jewelry design are all part of our expertise which we offer in our San Diego jewelry store.

Diamond Education

The four C's of a diamond - cut, clarity, color and carat weight



The better the proportions of a diamond, the more brilliant and fiery the diamond will be. Did you know that many diamonds are miscut to weigh more and to look larger than their well-cut counterparts? These stones will not have the fire and sparkle of a well-cut diamond.

The Ideal Cut from Jessop's is the most brilliant diamond of all. Ideal Cut describes a diamond that has been cut by a master diamond cutter with exactly placed facets to create the most splendid combination of luster, beauty, brilliance and fire. A diamond cut to Ideal proportions has light entering from any direction reflected totally through the top and then dispersed into an incomparable display of sparkling flashes and rainbow colors. Very few diamonds - actually, fewer than two percent -- are cut to the exact and mathematical precision of a true Ideal Cut.


Almost every diamond has naturally occurring imperfections or inclusions. The harder it is for a trained diamond grader, using a 10-power binocular microscope, to find these inclusions, the higher the clarity grade and the more valuable the diamond. A flawless diamond - a diamond with no inclusions visible at this magnification - is extremely rare.


For most diamonds, the whiter or more colorless a diamond, the more rare, valuable and desirable it is. Generally, diamonds contain tints of color, making the diamond look off-white, or producing a diamond that is yellowish, brownish or grayish.

Occasionally, diamonds of naturally occurring deeper color will come along. These diamonds are called fancy-colored diamonds. Some of the fancy colors are yellow, rich cognac brown, champagne and peach. Green and especially blue are colors considered extremely rare and extremely valuable when natural. At Jessop's, all fancy-colored diamonds are naturally colored.

Carat Weight

The fractions of a diamond's weight are described as points. One carat equals 100 points; a 50-point diamond is one-half carat. It takes more than a million mined carats to unearth a fine-quality 1-carat diamond - good reason for a 1-carat diamond to cost four or five times as much as the one-half-carat stone of equal quality. Large diamonds are so rare, value and price increase due to rarity.

To give you an idea of just how much carats weigh, 5 carats are the equivalent of one gram.

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