4Cs: What Is Diamond Clarity?

What Is Diamond Clarity?

Diamond clarity refers to the presence of internal flaws (inclusions) and surface flaws (blemishes) in a diamond. Diamonds are formed from carbon under high-temperature conditions, and during this process, some impurities may become trapped inside the diamond, and small cracks may appear on its surface.

Grading institutions evaluate these inclusions and blemishes to assign a clarity grade to each diamond. The fewer the imperfections, the higher the clarity of the diamond.

What Types of Internal and Surface Flaws Are Found in Diamonds?

Internal Flaws (Inclusions):

1. Cloud: A cluster of tightly grouped pinpoints, appearing as a foggy white or gray area, or resembling a powdery white patch.

2. Feather: Any crack or fracture within the diamond.

3. Included Crystal: Mineral crystals trapped inside the diamond.

4. Indented Natural: A growth mark from the rough diamond’s surface that forms a groove and remains under the polished facet after cutting.

5. Internal Graining: Irregular crystal growth in the diamond, visible as parallel lines, slanted lines, or wavy curves.

6. Knot: A crystal within the diamond that extends to the surface facets. Since the knot grows in a different direction from the host diamond, it can complicate polishing.

7. Needle: A long, thin crystal inclusion within the diamond, which can be white or dark in color.

8. Pinpoint: A tiny crystal, visible under 10x magnification as a small dot, typically white but occasionally black.

9. Laser Drill Hole: A mark left by laser drilling, a treatment used to improve the appearance of dark inclusions, creating a pathway from the diamond’s surface to the inclusion.

10. Bruise: An impact area showing root-like feather patterns, often appearing as a cottony structure when viewed from the side.

11. Cavity: A pit left on the diamond surface after a crystal has fallen out or been removed during cutting.

12. Chip: A shallow, curved opening on the surface, typically occurring after the diamond is polished.

Surface Flaws (Blemishes)

1. Abrasion: A series of tiny nicks along the facet edges, giving the edges a frosty appearance. These are caused by uncareful handling that leads to friction between diamonds.

2. Scratch: Fine, white lines on the diamond surface that can be straight or curved.

3. Nick: Small, shallow openings, often found along the girdle or facet edges.

4.Polish Line: Minor parallel lines left on the surface during polishing, appearing white or transparent. They can occur on any facet but do not cross over facet edges.

5. Pit: Tiny surface openings that appear as small white dots.

6. Lizard Skin: A wave- or ripple-like texture seen on polished diamond facets.

7. Natural: A portion of the diamond’s rough surface left intact on the finished stone.

8. Extra Facet: Additional facets not included in the original facet design, often added to remove a surface irregularity or as a polishing adjustment.

9. Rough Girdle: An uneven girdle surface with small pits or a grainy texture.

10. Surface Graining: Transparent lines on the polished surface caused by irregular crystal growth. Surface graining is linked to internal graining and can appear simultaneously.

Every type of flaw in a diamond is documented on its certificate, with specific symbols used to identify the type of inclusion or blemish. Colors are used to differentiate between internal and surface flaws: red represents internal flaws, while green indicates surface blemishes.

No two diamonds in the world are exactly alike, and the unique patterns of internal and surface flaws are the main reason for this. These characteristics are also clearly illustrated on the diamond’s certificate.

How Is Diamond Clarity Graded?

To evaluate a diamond’s clarity, professional graders examine the stone under 10x magnification to assess the number, size, location, type, and relief of its flaws. Based on this evaluation, the diamond is assigned one of 11 specific clarity grades. Additionally, all internal and surface flaws are marked on the diamond’s certificate, helping identify the stone as unique.

Factors Influencing Clarity Grading:

1. Size: The size of the flaws is the most critical factor in determining the clarity grade. Larger flaws have a greater impact on the diamond’s appearance.

2. Number: The more flaws a diamond has, the lower its grade. Even small flaws can significantly affect the diamond’s transparency and appearance.

3. Type: The type and depth of the flaws also play an essential role in grading. Certain types of inclusions can have a more noticeable effect than others.

4. Location: Flaws closer to the center of the diamond are more visible to the naked eye, leading to a lower clarity grade.

5. Relief: Relief refers to how noticeable the flaws are compared to the diamond itself. Higher contrast between the flaws and the diamond, such as darker inclusions, can result in a lower grade.

What Are the Specific Clarity Scales for Diamonds?

In 1953, the Gemological Institute of America (GIA) standardized the 4Cs, including a six category, 11-grade clarity scale, which is now used worldwide to classify diamond flaws. Below is the GIA diamond clarity scale:

1. Flawless (FL)

No internal or surface flaws visible under 10x magnification.

2. Internally Flawless (IF)

No internal flaws under 10x magnification, but minor surface blemishes that could be removed by polishing.

3. Very, Very Slightly Included (VVS1, VVS2)

Contains extremely tiny inclusions that are difficult to detect even for skilled graders under 10x magnification.

4. Very Slightly Included (VS1, VS2)

Inclusions are visible under 10x magnification but are very small and have minimal impact on the diamond’s appearance.

5. Slightly Included (SI1, SI2)

Inclusions are noticeable under 10x magnification and may be visible to the naked eye in some cases.

6. Included (I1, I2, I3)

Inclusions are obvious under 10x magnification and visible to the naked eye. These flaws may affect the diamond’s durability, transparency, and brilliance.

Diamonds with FL (Flawless) and IF (Internally Flawless) grades are extremely rare. Even in lab-grown diamonds, which typically have high purity, VVS (Very, Very Slightly Included) and VS (Very Slightly Included) grades are the most common, while diamonds below VS grade are less frequently seen in the market.

Because lab-grown diamonds are created in controlled environments that simulate natural diamond growth, there are fewer external factors affecting clarity. As a result, lab-grown diamonds generally have higher clarity compared to natural diamonds. However, even in these controlled conditions, small impurities can form during growth, which is why most lab-grown diamonds fall within the VVS to VS clarity range.

The clarity of a diamond plays a significant role in its selection, as it directly affects the diamond’s appearance, brilliance, and overall beauty, while also heavily influencing its value.

• If you seek perfection in appearance, brilliance, and quality, diamonds with FL, IF, or VVS grades are excellent choices. These are ideal for occasions requiring exceptional sparkle and flawless looks.
• For those looking to maximize size or color grade within a budget, VS-grade diamonds are a great option. Their inclusions are typically invisible to the naked eye, and they offer a good balance of quality and affordability.
• For jewelry worn infrequently or for consumers on a tighter budget, diamonds with lower clarity grades that still maintain good appearance can provide excellent value.

In general, choosing a diamond’s clarity requires balancing your budget, needs, and intended use while also considering other factors like color, carat weight, and cut.