Grading System

Established in 1931, GIA developed the International Grading System for accurately grading gemstones. It is an integral part of the diamond certification process. The GIA is trusted as the respected authority that educates and certifies gemologists. It takes a series of scientific tests and evaluations to perform the grading process on a diamond. Gemologists use sophisticated equipment to grade color, clarity, cut, and carat weight.

Color

Before grading a diamond, the first step is to determine if it is natural or synthetic. A color scale establishes a diamond's color and grades it from ‘D’ to ‘Z’. The ‘D’ grade is colorless while a ‘Z’ grade is light yellow to brown in color. The categories on the scale are colorless, nearly colorless, faint, very light, and light. Nearly colorless gemstones are widely used in jewelry. For accuracy in grading color, gemologists use a set of master gemstones that precisely match the color scale to compare and determine the grade of a gemstone.

Clarity

When the gemologist looks at a stone, he or she is looking for internal and surface inclusions, which are natural forming characteristics or byproducts of the gem’s formation. Each inclusion gives diamonds their unique ‘fingerprints’. This scale has 11 clarity grades from ‘flawless’ to ‘I3’. A flawless gemstone has no inclusions while the grade ‘I3’ has inclusions visible to the naked eye. An example of an inclusion is ‘VS’, which stands for a Very Small inclusion. Gemologists use a jeweler’s 10X magnification loupe and a microscope to see inclusions and spot diamonds that received treatment to enhance their appearance. Inclusions noted on the grading report are part of the diamond certification process.

Cut

This step of the grading process determines the beauty and appearance of the diamond. The five ratings on the scale are excellent, very good, good, fair, and poor. The round brilliant cut is the standard when determining and grading the cut of a diamond. However, the rating scale applies to any cut of diamond. In addition to cut, gemologists look at a diamond's light performance. The sparkle and brilliance of diamonds depend on their cut and polish, how light strikes the surface, and how much light returns to the eye from the diamond. All of these factors affect the appearance of a diamond.

Next, the diamond is rotated 360 degrees in order to create a 3-D model. Although there are no exact measurements that determine a well cut diamond, GIA uses a complex set of calculations to determine a diamond’s proportion. In addition to proportion, symmetry is another aspect of grading the cut of a diamond.

Carat Weight

One carat equals 200 milligrams or 1/5 of a gram in weight and larger stones are valued higher. For instance, a 1 carat diamond is worth more than four 1/4 carat diamonds put together. An electronic scale weighs to the fifth decimal place, and diamonds sold are at weights to the second decimal place-2.25 carats.

A grading report contains detailed information about the diamond and completes the diamond certification process. For access to the report, it is also online. As added insurance, a diamond can be laser inscribed with report number, message, or logo.

Why Certification

The purpose for diamond certification ensures that customers receive an accurate representation of diamond attributes and an assigned value according to the International Grading System criteria.

When purchasing a diamond, complete the diamond certification process and ask for the GIA certificate. As an added measure of assurance, confirm that the information on the GIA certificate by looking through a jeweler’s 10X magnification loupe. While diamonds are a symbol of lasting beauty, it is equally important to get what you pay for.

Author bio:

Ken Thomas is diamond jeweler and avid blogger who writes for numerous blogs including New Updates Weekly.

The following are five questions to ask when you are getting ready to purchase an engagement ring....

Diamond Engagement Ring

#1) What Is Your Budget?

Many couples can be tempted to go overboard financially when purchasing an engagement ring.  That is why it is best to decide upfront what your budget is for purchasing a ring and to stick to that budget no matter what.

#2) Do You Want Something Old Or Something New?

There are a lot of choices besides just the classic diamond solitaire engagement ring.  Many antique engagement rings are absolutely spectacular and can serve as a link to the past.  At the other end of the spectrum, there are many cutting edge modern engagement rings that are unlike anything that has ever been produced before.  So the truth is that there are lots of choices out there and lots of opportunities to pick something that will suit your particular style.

#3) What Kind Of Stone Do You Want?

An engagement ring does not have to have a diamond on it.  In fact, a growing number of couples are opting for other exotic stones rather than diamonds for their engagement rings.  For example, blue sapphire engagement rings are becoming very popular.  So don't be afraid to incorporate other gemstones into your engagement ring, and don't be afraid if you want to leave diamonds out of your ring altogether.

#4) Do You Know Your 4 C's - Cut, Clarity, Carat, and Color?

When looking at an engagement ring, you are going to want to ask about all four of these categories.  The cut of the diamond is more of a style choice, but the last three categories can have a huge impact on the value of the diamond you are choosing.  The truth is that two diamonds can look remarkably similar and yet have vastly different values.

If you are not familiar with the various grades used to judge the quality of a diamond, then we recommend that you get the following excellent guide by Nancy N. Schiffer: Before You Buy an Engagement Ring: With a 4-Step Guide for Making the Right Choice (Schiffer Book).

For much more on the 4 C's, please see another article that we did on this topic: "How To Buy A Diamond".

#5) What Metal Do You Want The Band To Be Made Out Of?

Most of the focus when purchasing an engagement ring is on the gemstones.  But the band is another very important consideration.  The three most common choices are gold, platinum and white gold, although many couples go another direction in order to save some money.

The truth is that picking out an engagement ring can be an exhilarating experience, but you can also get burned if you do not know what you are doing.  It is important to get educated and to do your homework.

For young couples that are working on a tight budget, sometimes you can still get a great ring and save money at the same time by shopping places like Ebay, Craigslist and Amazon.  When you do shop online, be sure to research the seller you are considering purchasing from to make sure that they are reputable.

Having purchased an engagement ring online myself, I can honestly say that it does work and you can get a lot more ring for your money than by shopping at the jewelry retailer down at the mall.

But wherever you buy your engagement ring, always be careful and always do your research.  If you protect yourself and if you are willing to put in the hard work to find just the right ring, you will have a better chance of ending up with something that you both will love for decades to come.