Willyn Villarica Jewelry

The Diamond Grading Process: A Comprehensive Guide

People love diamonds for many reasons, from their beauty to their symbolism. Diamonds are known for being Earth’s most complex natural material and for reflecting light in an exquisite way that creates a sparkling effect. In addition, as the world’s oldest gemstone, diamonds have been used as symbols of devotion and eternal love for centuries, making them beloved by couples getting engaged or married.

Ensuring you get the best value for your money is paramount when buying diamonds. However, with all the different diamond grades and associated gemological terms, this can seem daunting—especially for first-time buyers. To help you understand exactly what goes into grading a diamond, we’ve compiled this comprehensive guide on the diamond grading process. In this blog post, we’ll cover everything from the cut and clarity of a diamond to its color grade and carat weight so that you can be an informed buyer when shopping for diamonds. So let’s start by diving into one of the most crucial aspects of understanding diamonds: their 4 Cs!

What is Diamond Grading?

Diamond grading is the analysis of a diamond, which looks specifically at the stone’s 4Cs: cut, color, clarity, and carat weight. Grading is done to assess a diamond’s quality and value.

The process of grading diamonds includes a meticulous examination of each diamond by experienced gemologists who have expert knowledge in analyzing the details of the characteristics of each stone. This involves inspecting how light passes through it (called ‘light performance’), examining its proportions and symmetry closely with specialized tools, and assessing its texture under intense magnification.

A diamond with excellent grades will appear more beautiful due to its brilliance and hold higher value compared to those graded lower on any one or all four parameters. In addition, certification organizations like GIA and IGI use standard practices for objectively evaluating diamonds using international standards. Once assessed, these certificates also indicate what qualities affect most significantly what kind of visual appeal we can expect from a particular grade or combination of grades for different stones – which helps us make informed decisions before purchasing them!

How Diamond Grading Works

Diamond grading is a fundamental part of the gemology industry. It is a complex process that evaluates every facet of a diamond’s physical characteristics, from carat weight and cut to clarity and color.

When grading diamonds, professional graders look for four primary components: carat weight, cut, clarity, and color. To determine these traits, diamond graders employ various instruments such as microscopes or specialized lighting designed to bring out each characteristic in the most precise way possible.

An experienced grader must carefully examine every aspect of a diamond’s cut. This includes evaluating facets (polished surfaces), girdle thickness (the outer edge), symmetry (when all sides are equal), polish quality (finish on the surface), depth percentages (how far the light will penetrate stone), and table size (center flat facet). All these components work together to create the beauty of the diamond’s sparkle or “fire.”

Diamond Quality Factors: The 4Cs

When it comes to diamonds, the four Cs are the most important factors to consider. Carat weight, cut, color, and clarity all play a role in determining a diamond’s quality and value. Here’s a closer look at each:

  • Carat weight is how a diamond is measured and the stone’s size. The heavier the carat, the more expensive the diamond.
  • Cut is how well the diamond has been cut and includes the height, depth, angles, and other factors. A well-cut diamond will be more brilliant and have more fire than a poorly cut one.
  • Color is judged on a scale from D (no hue) to Z (a yellow-hued stone). Stones closer to D on the scale are rare and more expensive.
  • Clarity is how many blemishes or inclusions a diamond has on its surface or inside. Diamonds with few imperfections are rare (and therefore more expensive) than those with many flaws.

The Different Diamond Grading Scales Used

Diamond grading is the evaluation of a diamond’s quality based on characteristics like cut, color, clarity, and carat weight. It’s crucial to understand different grading scales used by various organizations before making purchase decisions. Here are other diamond grading standards used aside from GIA.

American Gem Society Grading Scale

Another popular diamond grading scale is the American Gem Society (AGS). This system grades diamonds from 0-10 using four criteria: cut design grade; polish grade; symmetry grade; and fluorescence intensity level. 0 being at the highest end of perfection for diamonds up to 10, which has significant structural problems that significantly impact its beauty or durability (if any).

European Diamond Grading Standard

There is also a European diamond grading standard known as the “4C” offered by De Beers Group: Cut & Polish Quality – 3 categories assessing reflectiveness & fire; Color Grade – 7 different shades from D – Z (D= whitest); Clarity Grades Level -9 different levels detectable even under magnification; Carat Weight -measured in metric carats with 1ct = 0.2 grams usually abbreviated ‘ct’ or ‘ctw.’

Each organization offers a unique approach to evaluating diamonds depending on their respective methods, so choosing one type over another ultimately boils down to personal preference.

Schedule an Appointment Today

Looking to get an appraisal for your valuable items?
Schedule an appointment today for a fair and accurate assessment!

Factors that Affect Diamond Grading

Diamond grading is assessing a diamond’s characteristics and assigning it an overall grade based on these factors. A diamond’s grade determines its value, beauty, and durability. The four main factors that affect a diamond’s grade are:


This refers to a diamond’s shape, symmetry, proportions, and overall finish. Its cut influences how much light reflects off of its surface, resulting in its brilliance or sparkle.


Natural diamonds come in many colors, from colorless to intense shades of yellow or brown. Colorless diamonds are more valuable because they allow more light to reflect off the stone than colored diamonds. However, some fancy colored diamonds, such as yellows, pinks, and blues, can be very rare, resulting in higher prices for those stones with exceptional grades for their respective colors.


This factor evaluates where inclusions (or blemishes) appear within the stone along with their nature and size to determine how visible they are when looking at the gem with 10x magnification under proper lighting conditions such as those used by gemologists performing grading services on diamonds prior to selling them. Clarity grades range from I1 – Flawless(FL). However, most commercially available jewelry will only find stones up to SI2-SI3 clarity grades due to cost/price reasons, as clarity affects price significantly when comparing two similar quality goods side by side.

Read More: Understanding Diamond Clarity

Carat Weight

This is simply referring to the weight of a diamond which directly translates into size & volume; therefore, higher carats tend to be larger than lower carats, albeit all having equal quality standards like cut/clarity, etc. Since diamond prices increase exponentially with large sizes, buyers should weigh their options carefully if budget is an issue. Multiple smaller stones may produce a more extensive spread for a lower expense than one bigger piece.

Choosing the Right Diamond Grader

Choosing the right diamond grader is a critical step in creating an accurate and reliable appraisal of diamonds. It requires considerable knowledge, training, and experience. A diamond grader must be certified by a prestigious organization to ensure they have adequate expertise.

When choosing a diamond grader, selecting someone who has received their accreditation from the Gemological Institute of America (GIA) is important. GIA is one of the most respected and trusted organizations for gemstone certification, offering rigorous curriculums for training students in gemology. They also use cutting-edge technology when evaluating stones and providing grading reports that include size, shape, color grade, and clarity grade information.

By finding a professional diamond grader who is both trained through GIA courses as well as highly experienced in working with various types of stones being graded according to The Four C’s standards, you can rest assured that any appraisals will come back detailing accurate facts needed when selecting diamonds or assessing pricing patterns at market level prices for secondary markets like auctions or estate sales.

Related: How to Get a Diamond Appraised

Reach out to Willyn Villarica Jewelry

The diamond grading process is complex, requiring various complementary technologies and professionals to ensure accuracy and precision. Although only some people need to understand the nuances of diamond grading, having a basic understanding can help you make smarter decisions when selecting diamonds. Willyn Villarica Jewelry has exceptional knowledge in this field and can provide tailored advice when searching for your perfect diamond. Willyn Villarica is your trusted partner for diamond-grading services, catering to clients around the globe. Our expertise and commitment to excellence ensure accurate and reliable assessments of your precious gemstones. It’s important to note that while we offer our services worldwide, clients are responsible for covering all travel expenses. Don’t miss out on the opportunity to have your diamonds expertly graded by Willyn Villarica.

To request information or schedule appointments, please feel free to contact us via email at admin@willynvillaricajewelry.com, you may also connect with us through our official Facebook (Willyn Villarica Jewelry) and Instagram (@willynvillarica_jewelry) accounts. Should you require immediate assistance, we are also accessible for direct communication at +63279497547.

  • Willyn Villarica

    Willyn Villarica, a third-generation jeweler from the Philippines, brings a wealth of expertise to the world of gemology and jewelry appraisal. As a licensed Graduate Gemologist, accredited by the prestigious Gemological Institute of America, she is not only a master of her craft but also holds the distinction of being the first Filipino member of the National Associ...

Leave a Comment