Diamond Education

Cut is widely considered the most important of the 4Cs because it has the greatest impact on a diamond's brilliance. A diamond's cut grade describes how well its facets interact with light — not the diamond's shape.

When a diamond is cut to ideal proportions, light entering through the top travels through the stone and reflects back out through the table, creating maximum brightness and fire. If a diamond is cut too deep or too shallow, light escapes through the sides or bottom instead of reflecting back to the eye, resulting in a duller appearance regardless of color or clarity.

Diamond color grading measures the absence of color. The scale runs from D (completely colorless) to Z (light yellow or brown), with most gem-quality diamonds falling between D and M.

Colorless diamonds are the rarest and most valuable because they allow the most light to pass through, maximizing brilliance and fire. As color grade decreases, diamonds take on a faint yellow or brownish tint that becomes more noticeable, particularly in larger stones or when viewed against a white background.

Clarity measures the presence of internal inclusions and external blemishes formed naturally as a diamond crystallizes. Most inclusions are microscopic and cannot be seen without magnification.

The clarity scale ranges from Flawless (FL), with no inclusions or blemishes visible under 10x magnification, down through Included (I), where inclusions may be visible to the naked eye. Diamonds graded VS (Very Slightly Included) or higher typically appear eye-clean, offering excellent value without visible imperfections.

Carat refers to a diamond's weight, not its size — one carat equals 200 milligrams. Two diamonds of equal carat weight can appear different in size depending on their cut proportions.

Because larger diamonds are rarer, price increases disproportionately as carat weight goes up. A well-cut diamond can appear larger than its actual carat weight thanks to how effectively it reflects light, which is why cut and carat should always be considered together.