When shopping for diamonds, one of the first factors you'll examine is the stone’s clarity, which plays a significant role in determining its value. Clarity, along with the other three "Cs" — Color, Cut, and Carat Weight — is essential in understanding the overall quality of the diamond.

However, simply looking at the diamond with the naked eye won’t necessarily reveal all of its imperfections, known as blemishes and inclusions. To identify these minute flaws, a jeweler's loupe, a small magnifying glass that offers 10-20x magnification, is required for a closer inspection.

What Are Diamond Blemishes?

Blemishes are imperfections that appear on a diamond’s surface, while inclusions are internal flaws. These external irregularities can occur during the manufacturing, handling, or wearing process. For instance, abrasions, nicks, scratches, and chips are all examples of blemishes that typically happen over time. On the other hand, certain blemishes, such as extra facets or burn marks, may occur during the cutting process.

While many blemishes are tiny and difficult to detect without magnification, they can affect the overall clarity grade of the diamond.

Common Diamond Blemishes

• Scratches: Thin, white lines on the surface of the diamond, usually light and not deep.
• Nicks: Small notches, often on the edge or facet junctions, that can be visible under magnification.
• Abrasion: Tiny nicks along the facets, which cause the diamond’s edges to appear fuzzy.
• Polish Lines: Fine grooves left on the surface from polishing, typically parallel and either transparent or white in appearance.
• Natural: A portion of the original rough diamond’s surface, often near the girdle, left intact during the cutting process.

Other Surface Imperfections

• Burn Marks: Hazy spots caused by excessive heat during polishing.
• Extra Facets: Additional facets that are not necessary for the cut but added for symmetry or other reasons.
• Surface Graining: Irregularities in the diamond's surface structure.
• Lizard Skin: Bumpy or wavy areas found on the surface of the diamond.
• Pit: A tiny hole that looks like a white dot on the diamond’s surface.

What Are Diamond Inclusions?

Inclusions, often referred to as a diamond’s “birthmarks,” are internal characteristics formed naturally during the diamond’s creation. These imperfections can vary depending on the geological conditions of the diamond’s origin. Some diamonds have more visible inclusions than others, and the type of inclusion can influence the clarity grade of the stone.

Types of Diamond Inclusions

• Mineral Crystals: Trapped crystals or minerals within the diamond, which can appear as white, transparent, or black spots. They can affect the stone’s overall brilliance.
• Clouds: Small clusters of tiny crystals or pinpoints that can create a cloudy appearance.
• Indented Natural: A dip or indentation in the polished surface that’s caused by a natural feature from the rough diamond.
• Needles: Long, thin, needle-like inclusions that resemble streaks of light inside the diamond.
• Twinning Wisps: Features that look like stretch marks inside the diamond, often found in fancy-shaped stones.
• Knots: Crystal inclusions that appear as knots within the stone.

The Worst Diamond Inclusions to Avoid

Some inclusions significantly reduce a diamond’s brilliance and overall appearance. These include:

• Black Crystals or Carbon Spots: Dark spots that prevent light from passing through the diamond and reduce its sparkle.
• Top or Center-Located Inclusions: Inclusions located in the center or top of the diamond can negatively affect its shine and clarity.
• Long Needles or Cracks: These can create weak points in the diamond, making it more prone to splitting.
• Large Clouds: If clouds occupy a significant portion of the diamond, they can make the diamond appear milky or hazy, reducing its clarity.

What Causes Black Spots in Diamonds?

Black spots are natural flaws that occur during a diamond’s formation when carbon atoms don’t fully crystallize. These spots, although permanent, are formed deep within the diamond and aren’t caused by cutting or handling. Black spots will lower the clarity grade and cannot be removed without compromising the integrity of the stone.

Do Diamonds Have Pits?

Pits, or small holes, may appear on a diamond’s surface, particularly on the table facet. While these tiny imperfections are often undetectable to the naked eye, they can reduce the diamond's overall clarity when visible.

Conclusion

When buying a diamond, it’s essential to understand the impact of blemishes and inclusions on the clarity and value of the stone. While some imperfections are more visible than others, a professional evaluation will give you a clear picture of the diamond’s true quality. By choosing a diamond with minimal blemishes and inclusions, you ensure that it remains stunning and sparkly for years to come.