Diamonds at Coin Mart

A diamond is one of the most valuable things you can hold in your hand, and one of the easiest to misunderstand. Knowing how diamonds are actually valued protects you whether you are buying one or selling one. Here is what matters.

The 4Cs, explained simply

Every diamond is graded on four qualities. Together they determine its value.

Cut. How well the diamond is cut, its proportions and finish, which decides how much it sparkles. Cut is often considered the most important of the four, because a poorly cut diamond looks dull no matter how good the rest is.

Color. How colorless the diamond is, graded on a scale from colorless down to noticeably tinted. The more colorless a white diamond, the rarer and more valuable it generally is. Fancy colored diamonds, like yellow or pink, follow their own separate scale.

Clarity. The presence of tiny internal marks, called inclusions, and surface marks, called blemishes. Fewer and smaller marks mean higher clarity and higher value. Many are invisible without magnification.

Carat. The weight of the diamond. Larger diamonds are rarer, so price rises steeply with size, not just steadily.

Why an expert assessment matters

Two diamonds can look similar to the eye and be worth very different amounts. The differences often come down to details you cannot judge without training and tools, the quality of the cut, subtle color, inclusions under magnification. That is why an honest expert assessment is the difference between paying or receiving a fair price and being taken advantage of.

At Coin Mart, we assess every diamond honestly and explain what it actually is. After more than 65 years in fine jewelry, our reputation depends on getting that right.

Certified diamonds

An independent grading report from a respected lab gives you a documented, unbiased assessment of a diamond's 4Cs. A certified diamond takes much of the guesswork out of buying, because an expert third party has already graded it. We are glad to walk you through what a report means for a specific stone.

Buying and selling diamonds at Coin Mart

Buying. Explore diamond jewelry selected for quality you can actually see, with an honest account of each stone.

Selling. Have a diamond or diamond jewelry to sell, or a piece you inherited? Bring it in for a fair, expert evaluation. Learn about selling gold and jewelry →

Looking for a ring specifically? See our engagement rings section.

Back to Fine Jewelry →