Diamond Clarity Grading System
Diamond Clarity Grading System

Diamond clarity explained for New Zealanders

the four “C”s of diamond quality - diamond clarity

what is diamond clarity?

If you’re in the market for buying a diamond, you’ve most likely heard people talk about a diamond’s ‘clarity’. Clarity is one of The Four “C”s grading diamond quality, the others being carat, colour, and cut. Out of the 4 C’s of diamond quality (colour, clarity, carat weight, and cut), clarity is perhaps the most misunderstood term yet it has a major impact on a diamond’s value and therefore price so it’s worth taking a moment to get your head around it.

Diamonds are formed deep within the earth, under extreme heat and pressure so virtually all of these sought after gem-stones contain "birthmarks" which are small imperfections inside or on the surface. Diamond clarity refers to the presence and visual appearance of internal characteristics of a diamond called inclusions, and surface flaws called blemishes within a diamond caused during its formation or the cutting process.

Evaluating diamond clarity involves determining the number, size, relief, nature, and position of these characteristics, as well as how these affect the overall appearance of the stone. While no diamond is perfectly pure, the closer it comes, the higher it's value.

terms that refer to diamond clarity

diamond inclusions

During the process of surfacing under such tremendous pressure, tiny imperfections develop within the crystal structure. These flaws that occur internally are called inclusions and the more inclusions a diamond holds, the lower the diamond grade. Most inclusions that are present in gem-quality diamonds do not affect the diamonds' performance or structural integrity and are not visible to the naked eyes (When diamonds are graded, they are magnified at 10x power).

Inclusions may be crystals of a foreign material or another diamond crystal, or structural imperfections such as tiny cracks that can appear whitish or cloudy. Large clouds can affect a diamond’s ‘sparkle’ or ability to transmit and scatter light. Large cracks close to or breaking the surface may reduce a diamond’s resistance to fracture. There are several different classifications of inclusion types which basically consist of:

  • Clouds
  • Feathers or Needles
  • Internal crystals or minerals
  • Knots
  • Cavities
  • Cleavage
  • Bearding
  • Internal graining
  • Pinpoint
  • Laser lines

The diamond industry uses the term “internal characteristics” instead of “inclusions”. These characteristics can come in every shape, colour, and nature, therefore, each diamond is as individual as a fingerprint and no two are the same.

diamond blemishes

Blemishes are flaws found on a diamonds outer surface and they occur after a diamond’s formation, during the cutting, mounting, and wearing of a polished diamond. Extra facets, polish lines (thin parallel grooves and ridges) or burns (from excessive heat on the polishing wheel during cutting) are examples of blemishes introduced during the manufacturing process to raise the clarity grade of a stone.

Nicks, scratches, chips and abrasions are examples of blemishes introduced during the handling, mounting or wearing of a diamond. Chips are shallow openings where part of the diamond was broken off, most often at the girdle edge. Some terms referring to the types of blemishes are:

  • Polish lines
  • Grain boundaries
  • Naturals
  • Scratches
  • Nicks
  • Pits
  • Chips
  • Breaks
  • Dark spots
  • Light spots

All of these factors are considered together, as the stone must be graded as a whole based on the entire appearance. Once these questions are answered, a clarity grade can be given to the diamond, In the rarest and most expensive diamonds, the inclusions are too tiny to see even at 10x magnification in good light, which is why these stones are called "flawless" (FL) or "internally flawless" (IF) according to the quality analysis system of the Gemological Institute of America. At the other end of the scale are "imperfect" stones (I grades) with visible faults that mar their natural beauty.

diamond clarity grades

A clarity grade is assigned based on the overall appearance of the stone under ten times magnification.

the GIA diamond clarity grading system

o FL (flawless) - No external marks or internal inclusions visible to a trained eye under 10x magnification.
o IF (internally flawless) - Only minor surface blemishes but no internal inclusions visible to a trained eye under 10x magnification.
o VVS1, VVS2 (very, very slightly included) - Few, very small inclusions and/or finish faults, difficult for a trained eye to see under 10x magnification. Typical flaws include tiny pinpoints, faint clouds, tiny feathers, or internal graining.
o VS1, VS2 (very slightly included) - Very small inclusions and/or finish faults, somewhat difficult for a trained eye to see under 10x magnification. Typical flaws include crystals, feathers, distinct clouds and groupings of pinpoints.
o SI1, SI2 (slightly included) - Small inclusions and/or surface blemishes are easily seen under 10x magnification, but not visible face-up to a naked trained eye. Typical flaws include crystals, clouds and feathers.
o I1 (imperfect 1) - Inclusions and/or finish faults visible under 10x magnification, but hard to see with the naked human eye. Little effect on the brilliance of a stone.
o I2 (imperfect 2) - More and/or larger inclusions and surface blemishes are easily seen without 10x magnification. Some diminished brilliance within the stone.
o I3 (imperfect 3) - Many and/or very large inclusions and surface faults are easily seen without 10x magnification. The severity of the inclusions obviously disfigures the stone. Rarely used for jewellery purposes (most often used as industry diamonds).

Most are tiny imperfections that do not affect a diamond's brilliance. A common misconception about clarity is that it has a large impact on the sparkle of a diamond. It often isn't until you reach the bottom level of "I" categories that imperfections begin to detract from the beauty of the diamond. Don't be concerned if the clarity of the diamond you choose is not near the top the scale.

For a large majority of diamonds, it is the cut, polish and symmetry of the gemstone that are key factors to determine how much a diamond sparkles, so going further up the clarity scale can make a difference in price but not necessarily an improvement in sparkle.

choosing your diamond

Remember that diamond clarity is just one of the four characteristics you should consider before you buy a diamond. Consider diamond colour, diamond cut, diamond carat weight, price and other factors. Your quest to purchase a diamond is kind of like a large jigsaw puzzle -- it's only when all the pieces of the puzzle fall into place that you find the perfect diamond for you.

Your jeweller can offer advice about diamond clarity and choosing the right diamond for you. Aurum Fine Jewellery offers quality at an affordable price. The team at Aurum are happy to answer any of your questions about clarity or any other aspects of a diamond. We are here to clearly explain the differences in clarity grades and to help you understand how to use them when choosing your perfect diamond. We welcome all enquiries.

location & hours

Aurum Fine Jewellery is by appointment only. Please Book an appointment with Aurum fine jewellery  at a time that suits you. Online consultations via Zoom, Google or Skype are welcome. We have convenient off-street parking right at our front door. Alternatively email us or phone: 09 3781 335.

The Ponsonby studio at 89 College Hill is open for appointments from 10am to 4pm Tuesday to Saturday, an ideal time for couples wanting to choose a special piece together.

Tax and Duty Free purchases can be arranged. Payment by bank deposit, cash, Visa, Amex, MasterCard, Bitcoin. 6-12 months interest-free finance is also available.



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