Learn the Tools of the Trade

The diamond certification process is a meticulous one with professional appraisers examining finished diamonds in minute detail.  Every aspect of the polished diamond is scrutinized, including the 4 c’s and beyond: diamond cut, diamond carat weight, diamond color and diamond clarity.  After an extensive evaluation a final comprehensive diamond certification is given.

The first step is to clear away any diamond residue left over from the cutting and polishing of the diamond.  Once the diamond is free of any leftover particles, specific tools are used to arrive at the exact grading.  The most familiar tool used in this process is the jeweler’s loupe but as you can imagine there are many others.  Here are just a few of the tools used you may never have heard of.

Dark Field Magnifier

A dark field magnifier is used in determining clarity

As a tool, the dark field magnifier is a type of loupe used for examining diamonds and other gemstones against a black background. The dark backdrop makes it easier to see internal inclusions or cracks and any surface scratches or marks.  The use of an external light source, such as the focused light of a flashlight, is aimed across the diamond.  This illumination highlights the diamond against the dark field for close examination.

Diamond Refractometer

A Refractometer is used to examine cut

A refractometer is a tool used to determine the refractive index (RI) of diamonds and gemstones.  The RI measures the change in the speed of light through the diamond and is a key measurement in determining the quality of the cut of a diamond.  In simple terms is measures the shine.  The diamond is covered with RI fluid and then viewed through the eyepiece of the refractometer to see the shadow lines created by each facet.  The measurements and readings of the shadow lines reveal the exactness of each facet and its reflective quality.  Normal incandescent light will disperse and create an unclear line on the scale.  Instead focused light is used to create a single and sharp line.


A polariscope is used to examine cut and clarity

A polariscope reveals patterns of light.  More specifically it’s used to show an appraiser the path of a beam of light through the diamond.  Examining a diamond through a polariscope gives a clear picture of diamond inclusions and enables the diamond appraiser to differentiate solid inclusions from negative inclusions.  These inclusions indicate flaws in the diamond and affect the grading and overall clarity of the diamond.

Jeweler’s Loupe & Diamond Scope

Loupes & scopes are used to mainly examine clarity

A jeweler’s loupe is used to determine clarity and whether any inclusions exist in the diamond.  Loupes come with many options for the level of magnification with the most common being 10x.  The basic 10x loupe is usually a triplet, meaning the loupe has three lenses.  Learn about how to use a jewelry loupe.

For the purpose of certifying diamonds however a more powerful tool is usually used, called a diamond scope.  Referring to the image on the right of hearts & arrows you can see the detailed image that a scope provides.  It’s basically an x-ray.  As you know with human x-rays there is nothing to hide.  The scope shows every flaw up close and personal.  When you look at an image through a scope you can really understand why no two diamonds are exactly alike.  In turn you can understand to appreciate the wonders of mother nature and that whatever stone you  choose will be one of a kind.

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