Education

 

Education

The 4 C's of Diamonds When purchasing diamonds it is always a good idea to be educated about your purchase. The Gemological Institute of America (GIA) grades diamonds according to the four Cs: cut, color, clarity and carat weight. The interplay of the four Cs determines a diamond's value. A diamond's value rises as its size, or carat weight increases likewise the value will increase or decrease dependent upon the color, clarity and cut. Carat – The carat weight determines how large and heavy the diamond is. Usually, the larger the stone, the more costly it is. Carat is often confused with size even though it is actually a measure of weight. Sometimes, you might think a larger diamond appears more brilliant than a smaller one. This is because light must travel a greater distance through a larger diamond. The result is a prism effect that your eye registers as more brilliance and fire. One carat is equivalent to 200 milligrams. One carat can also be divided into100 "points." A .75-carat diamond is the same as a 75-points or a 3/4 – carat diamond. Larger diamonds are found relatively infrequently in nature and are therefore more valuable. A 1-carat diamond costs exactly twice the price of a 1/2-carat diamond, right? Wrong. Since larger diamonds are found less frequently in nature, a 1-carat diamond will cost much more than twice as much as a 1/2-carat diamond, assuming color, clarity and cut remain constant. Cut and mounting can make a diamond appear larger (or smaller) than its actual weight. So shop around and talk to your jeweler to find the right diamond and setting to optimize the beauty of your stone. The term carat is a derivative of the word carob. Carob seeds are surprisingly similar in weight to one another; thus they were used in ancient civilizations as the reference tool to measure the weight of a diamond. One carob seed equaled 1-carat. Many people confuse carat and karat.Carat refers to the weight of a diamond while karat refers to the purity of gold (not the weight). You might see a 1-carat diamond set in 18 karat gold, for example. Clarity – Clarity refers to the number of spots or inclusions in a diamond. When light enters a diamond, it is reflected and refracted out. If there is anything disrupting the flow of light in the diamond, such as an inclusion, a proportion of light will be lost. As a result, brilliance could be diminished. The number of inclusions can determine the degree of brilliance lost. Inclusions, which are sometimes referred to as "nature's fingerprints," are usually not visible to the naked eye unless magnified. Inclusions are ranked on a scale of perfection, known as clarity, witch was established by the Gemological Institute of America (GIA). The clarity scale, ranging from FL (Flawless) to Included (I), is based on the visibility of inclusions at a magnification of 10x.

Grading Chart

Grading Chart

The position of inclusions can affect the value of a diamond. There are very few flawless diamonds found in nature, thus these diamonds are much more valuable. What's the difference between VVS1 and VVS2 or SI1 and SI2? The numbers represent levels within each grade. The 1s will be cleaner (have fewer or smaller inclusions) than the 2s. This allows for more specific grading categories. Inclusions are natural identifying characteristics such as minerals or fractures, appearing while diamonds are formed in the earth. They may look like crystals, clouds or feathers. The position of inclusions can affect the value of a diamond. You may not notice a significant difference between a VS1 and a VS2. However, you should consider the number, size, brightness, nature and position of the inclusions. Some inclusions can be hidden by a mounting, thus having little effect on the beauty of a diamond. An inclusion in the middle or top of a diamond could impact the dispersion of light, sometimes making the diamond less brilliant. Cut – The proper cut enhances a diamond's capacity to reflect light and makes it sparkle more. Diamonds come in all shapes and sizes. It depends on your personal preference. Cut refers to the angles and proportions a skilled craftsman creates in transforming a rough diamond into a polished diamond. Nature determines so much about a diamond, but is takes a master cutter to reveal the stone's true brilliance, fire and ultimate beauty. Based on scientific formulas, a well-cut diamond will internally reflect light from one mirror-like face to another and disperse and reflect it through the top of the stone. This results in a display of brilliance and fire. Diamonds that are cut too deep or too shallow lose or leak light through the side or bottom, resulting in less brilliance and ultimately, value.

Gem Terms

Gem Shown with Common Terminology

Cut is the only one of the 4Cs that is influenced by the human hand. The rest (color, clarity, carat) are created naturally as diamonds form in the earth. Diamond cutting requires great skill and training. The cutter must polish tiny surfaces known as facets onto the rough diamond. This process is what creates the crown, culet, table, girdle and pavilion of the diamond.The facets, when arranged in precise proportions, will maximize brilliance and sparkle. To cut a diamond perfectly, a craftsman will often need to cut away more than 50% of the rough diamond. Cut also refers to the shape of a diamond – round, marquise, pear, or heart for example. Since a round diamond is symmetrical and capable of reflecting nearly all the light that enters, it is the most brilliant of all diamond shapes and follows the proportion guidelines above.

Ideal Diamond Proportions

Ideal Diamond Proportions

Shapes other than round do not follow the proportion guidelines shown. Non-round shapes, also known as "fancy shapes", will have their own guidelines to be considered well-cut.

Correct Cut Illustrated

Correct Cut Comparison

Cut and cutting style work in harmony to create a diamond's brilliance. Cutting style is categorized into three basic types: step-cut, brilliant-cut and mixed-cut. The difference among these three types is the facetting arrangement of each style.

Diamond Cut Terminology

Diamond Cut Terminology

Color – Most diamonds contain slight traces of yellow or brown and the more colorless a diamond is the greater its value. Diamonds are found in almost every color of the rainbow, but white-colored diamonds remain most popular. Diamonds are graded on a color scale established by the Gemological Institute of America (GIA) which ranges from D (colorless) to Z.GIA Color ScaleColor differences are very subtle and it is very difficult to see the difference between, say, an E and an F. Therefore, colors are graded under controlled lighting conditions and are compared to a master set for accuracy. Truly colorless stones (D) are extremely rare and consequently extremely valuable, yet color ultimately comes down to personal taste. Ask a jeweler to show you a variety of color grades next to one another to help you determine your color preference. Nature has also created diamonds in intense shades of blue, green, yellow, orange, pink or – rarest of all – red. These diamonds are called 'colored fancies' and are extremely rare and highly treasured.