Lesson Category: gemmology

You will learn about the intricate process and the importance of cut in determining a diamond’s beauty and value. In this lesson, you will explore the various shapes, cutting styles, and dimensions of diamonds, as well as understand the ideal cut based on Tolkowski’s findings for maximum light return.

Dive into the details of each facet, from the table facet to pavilion main facets, and understand the significance of the girdle thickness in determining the quality of a diamond. Learn about the meticulous process of cutting a diamond by hand, which involves multiple specialists such as inspectors, blockers, bruters, cross cutters, and brillianteers.

Gain insights into the importance of angles and proportions in diamond cutting, as well as how different cuts affect light reflection and refraction within the stone. By the end of this lesson, you’ll be able to make an informed choice regarding diamond cuts and appreciate the stunning craftsmanship that goes into creating these exquisite gems.

In this lesson, learners will explore the concept of carat weight and its importance when dealing with diamonds and coloured stones. They will discover the origin of the term “carat” which came from the carob seed used as a measure of weight around 100 BCE. With the metric system, one carat is now equal to 0.2 grams. Students will understand that diamonds and other gemstones are measured in points, where 100 points make a carat. The lesson demonstrates various sizes of diamonds from 0.01 carat (1 point) up to 4 carats, including their diameters, and explains how the price increases exponentially as the carat weight increases.

The lesson also explores how jewellers create clever designs that combine multiple smaller diamonds to give the appearance of a larger carat diamond at a more affordable price. Learners will examine how to compromise on colour, clarity, and carat weight to find a beautiful yet cost-effective piece of jewellery. Finally, the lesson touches on marketing techniques used by jewellers to show affordability in jewellery designs, emphasizing the importance of understanding the actual size and carat weight of the diamonds featured in advertisements. By the end of this lesson, students will have a better grasp on carat weight and its significance when making informed decisions about purchasing diamond jewellery.

Now you will explore the importance of clarity in diamonds and gemstones, focusing on internal characteristics (inclusions) and external characteristics (blemishes). The lesson highlights various types of inclusions, such as feathers, included crystals, pinpoints, clouds, needles, chips, cavities and bearding, and explains how they can impact the value and beauty of a gemstone. Various diamond grading systems around the world are discussed, emphasizing the use of 10x magnification for clarity grading.

You will become familiar with the different grading categories, including Flawless, Internally Flawless, VVS1, VVS2, VS1, VS2, SI, I1, I2, and I3, and understand the distinctions between them. The lesson also addresses the concept of compromising on color and clarity to get a larger diamond within a budget, ultimately aiding learners in making informed decisions when buying diamonds.

Welcome to the next section on diamond assessment! In this section, you will learn how to assess the value of diamonds and make informed purchases. Through detailed explanations and examples, you will gain a better understanding of how to grade diamonds for colour, clarity, cut, and carat weight. You will also learn about the various influencing factors that can affect a diamond’s value, such as its setting and metal type. 

In this first lesson, you will learn about the differences between assessing coloured stones and diamonds, and why colour grading is so important when it comes to diamonds.

The digital handout for the second section “Value Factors in Diamonds” is available for download in the Materials tab above.

Discover the fascinating world of diamond fluorescence! You’ll learn that approximately 30% of natural diamonds fluoresce, typically under long wave UV light, emitting a beautiful chalky blue color. Understand how varying degrees of fluorescence can affect a diamond’s appearance, sometimes causing a milky look but not always being visible under normal lighting conditions.

Explore how fluorescence occurs when atoms are excited and emit energy in different colors, with the majority of colorless diamonds displaying a bluish hue. You’ll learn that other colors, such as yellow and red, are also possible. Delve into the difference between fluorescence and phosphorescence, where the latter involves atoms remaining excited even after the UV light is removed, continuing to emit light for a short time.

Get acquainted with famous diamonds, such as The Hope Diamond, which exhibits extraordinary phosphorescence. By the end of this lesson, you’ll gain a greater appreciation and understanding of the captivating phenomenon of diamond fluorescence and phosphorescence, broadening your knowledge of gemstones and their unique properties.

In this lesson, you will gain a deep understanding of the differences between diamond stimulants and synthetic diamonds. You will learn about the properties of diamond simulants, how they differ from natural and synthetic diamonds, and how to identify them. The lesson covers both natural and man-made diamond simulants, including corundum and spinel. You will also learn about the chemical composition and crystal structure of diamonds, as well as the latest technology used to create synthetic diamonds.

In this lesson, you will learn about the three main attributes of diamonds: beauty, durability, and rarity. You will discover the natural octahedron shape of diamonds and how it contributes to their unique beauty. You will also explore the importance of diamond cutting and how it affects their brilliance, dispersion, and scintillation. Additionally, you will gain an understanding of the rarity of coloured diamonds and how it impacts their value.

In this chapter about diamonds, you will learn everything you need to know from diamond history, sources to their attributes and value. You’ll also discover the difference between simulants and synthetic diamonds, as well as how to assess the value of diamonds using the four C’s of diamond grading.

In this first lesson, you will learn about the fascinating history of diamonds, including their discovery in India and the impact of the South African diamond industry. You will also explore the different parts of the world where diamonds are sourced today and gain insights into the characteristics that make diamonds so unique.

The digital handout for this first Section “Diamond & Diamond Simulants” is available for download in the Materials tab above.