GIA • Gemological Institue of America

GIA is the largest, most respected nonprofit source of gemological knowledge in the world.

GIA exists to connect people to the understanding of gems. As a long-standing scientific authority, GIA is not only a unique source for diamond knowledge, its grading reports inspire confidence wherever they appear.

GIA's commitment to protecting diamond buyers inspired the Institute to create the 4Cs and the International Diamond Grading System™. These methods are the universal benchmarks by which all diamonds are judged. As the birthplace of these standards, and with its investment in continued gemological research, GIA's authority is unequaled.

The world's most respected retailers, museums, auction houses and private collectors rely on the expertise of GIA graders to assess, grade and verify their gems. They recognize the importance of complete, unbiased, scientific information in gem assessment, and absolutely trust GIA to provide it.

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The Four "Cs"

Every diamond is a miracle of time and place and chance. Like snowflakes, no two are exactly alike.

Until the middle of the twentieth century, there was no agreed-upon standard by which diamonds could be judged. GIA created the first, and now globally accepted standard for describing diamonds: Color, Clarity, Cut, and Carat Weight. Today, the 4Cs of Diamond Quality is the universal method for assessing the quality of any diamond, anywhere in the world.

The creation of the Diamond 4Cs meant two very important things: diamond quality could be communicated in a universal language, and diamond customers could now know exactly what they were about to purchase.

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The Cut of a Diamond

Diamonds are renowned for their ability to bounce and reflect light and sparkle so intensely. Precise artistry and workmanship are required to fashion a stone so its proportions, symmetry, and polish deliver the magnificent return of light only possible in a diamond. Cut defines the relationship a diamond has with light through three attributes:

  • Brightness: Internal and external white light reflected from a diamond
  • Fire: The scattering of white light into all the colors of the rainbow
  • Scintillation: The amount of sparkle a diamond produces, and the pattern of light and dark areas caused by reflections within the diamond

There are many more specific and technical characteristics that go into making the perfect cut for a diamond, which can be found at the GIA website linked below.

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The Color of a Diamond

The diamond color evaluation of most gem-quality diamonds is based on the absence of color. A chemically pure and structurally perfect diamond has no hue, like a drop of pure water, and consequently, a higher value. GIA's D-to-Z diamond color-grading system measures the degree of colorlessness by comparing a stone under controlled lighting and precise viewing conditions to Masterstone stones of established color value.

GIA's diamond D-to-Z color-grading scale is the industry's most widely accepted grading system. The scale begins with the letter D, representing colorless, and continues, with increasing presence of color, to the letter Z.

Many of these color distinctions are so subtle that they are invisible to the untrained eye; however, these distinctions make a very big difference in diamond quality and price.

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The Carat Weight of a Diamond

Diamond carat weight is the measurement of how much a diamond weighs. A metric "carat" is defined as 200 milligrams. Each carat can be subdivided into 100 'points' which allows precise measurements to the hundredth decimal place. A jeweler may describe the weight of a diamond below one carat by its 'points' alone and may refer to a diamond that weighs 0.25 carats as a 'twenty-five pointer'; greater than one carat are carats and decimals - 1.08 carats.

All else being equal, diamond price increases with diamond carat weight, because larger diamonds are rarer and more desirable. But two diamonds of equal carat weight can have very different values (and prices) depending on three other factors of the diamond 4Cs: Clarity, Color, and Cut.

It's important to remember that a diamond's value is determined using all of the 4Cs, not just carat weight.

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The Clarity of a Diamond

Natural diamonds are the result of carbon exposed to tremendous heat and pressure deep in the earth which can result in creating 'inclusions' and 'blemishes.' While no diamond is perfectly pure, the closer it comes, the higher its value. The GIA Diamond Clarity Scale has 6 categories, some of which are divided, for a total of 11 specific grades.

  • Flawless (FL): No inclusions or blemishes visible under 10x magnification
  • Internally Flawless (IF): No inclusions visible under 10x magnification
  • Very, Very Slightly Included (VVS1 and VVS2): Inclusions so slight they are difficult for a skilled grader to see under 10x magnification
  • Very Slightly Included (VS1 and VS2): Inclusions are observed with effort under 10x magnification, but can be characterized as minor
  • Slightly Included (SI1 and SI2): Inclusions are noticeable under 10x magnification
  • Included (I1, I2, and I3): Inclusions are obvious under 10x magnification which may affect transparency and brilliance

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The Shape of a Diamond

Here are a few things to keep in mind when considering shape:

Choosing the right shape for your diamond, or any gemstone really depends on many things such as personal taste, stone size, quantity, if any, surrounding stones, metal, and other personal variables. The point really is that you can get whatever shape diamond you'd like, but if you're not sure then it's a good idea to let Kailee and Rebecca help you decide when you meet with them.

Shapes with fewer facets, such as emerald or square, require higher clarity. The fewer the facets, the more visible any inclusions will be.

If they prefer clean, modern lines in furniture, they'll react well to the same aesthetic in Emerald or Square shapes. If they tend towards the traditional, a round shape rarely misses.

About Conflict Diamonds

You've probably heard the term "conflict-free" when the talk is about diamonds. Other terms you might have heard on the topic are blood diamonds, conflict diamonds, converted diamonds, hot diamonds, and war diamonds. Basically, conflict-free diamonds are ones that are mined and sold ethically in specific countries. Most blood diamonds come from Africa, where they are mined and sold for the purpose of financing war.

By 2004, the World Diamond Council noted that the illegal trade of these diamonds was down to about 1%. The industry has taken a strict stance in not selling these diamonds and thereby not supporting the killing and deaths of anyone in these wars. If you stop to think about the true beauty of a diamond, it seems ironic, if not disturbing, to think that something so beautiful could be associated with acts so heinous and cruel as in war.

No one should ever look around their neck or down at their hand to see a gemstone that cost lives. At Hamilton Jewelry Inc. we only work with conflict-free diamonds to ensure that the stone you see every day is one of an ethical and decent background; allowing you to simply enjoy the beauty of the stone itself.