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A Brief History of Diamonds

Diamonds have a rich history. The earliest diamond deposits date back 900 million years. To put that into perspective, the Earth is approximately…

Summary of Diamond Properties

For this lesson, all that is required is for you to visit our gemstone encyclopedia article about Diamonds and briefly familiarize yourself with…

Optical Properties of Gemstones

Step 2: Advanced Gemology Lesson 1 Back to syllabus We tend to take light for granted. It’s such a common thing we experience every day. Rarely…

A Brief History of Famous Diamonds

No other precious gem is as familiar — and coveted — as diamond. Clear as water yet sparkling with colors, diamonds are the subject of many stories…

Aquamarine Grading and Pricing

Like many other gems, aquamarine is judged based on the Four Cs: color, clarity, cut, and carat. In this article, we’ll cover how each factor influences…

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A Brief History of Diamonds

Summary of Diamond Properties

Optical Properties of Gemstones

A Brief History of Famous Diamonds

Aquamarine Grading and Pricing

An Introduction to Gemstone Inclusions

Identifying Inclusions of Specific Gems

What Does the GIA Colored Gem Grading Code Mean?

Gem Price Guide