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Diamond education

The 4Cs, grading reports and light performance, explained with the numbers that change what you buy.

How Can You Tell if a Diamond Is Real?
FeaturedHow Can You Tell if a Diamond Is Real?Clara Whitmore, 5 min read
A goldsmith's hands working on filigree at a cluttered bench, archival black and white photographWillem van de Poll · CC0

What the grades mean in real light

Grades are made at a bench under 10x magnification. Here is what they mean across a dinner table.

Start with the 4Cs
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Education

What Exactly Is an IGI Certified Diamond?

You will see IGI on most lab-grown stones. Who IGI is, what its report tells you and when you may prefer GIA.

Clara Whitmore3 min read
Education

RapNet Alternative: 3 Ways to Access “Wholesale” Diamond Data (Free)

No RapNet membership? Three free ways to see wholesale-style diamond data, and what each one can and cannot tell you.

Julian Vance3 min read
Education

5 Tools You Need to Inspect a Diamond Like a Pro

The person behind the counter has the light, the jargon and the tools. These five even the odds before you pay.

Clara Whitmore4 min read
Education

Lab Grown Diamonds: The Data-Driven Truth (2026)

Lab-grown diamonds are real diamonds at a lower price. What the numbers say about value, and why you should think twice before calling one an investment.

Julian Vance3 min read
Education

VS1 vs VS2 Diamond Clarity: Does the Data Justify the Difference?

Can you actually see the difference between VS1 and VS2? What the grades mean, what the gap costs and when paying more makes sense.

Clara Whitmore3 min read
Education

The 4Cs of Diamonds: A Data-Analyst’s Guide to What Actually Matters

The 4Cs are not equal. Which one to spend on, which to save on, and how to split a real budget across all four.

Julian Vance4 min read

Questions about education

What are the 4Cs?
Cut, color, clarity and carat weight: the grading system GIA introduced and labs worldwide now use to describe a diamond's quality.
Which color grades look white?
On the GIA scale D–F are colorless and G–J near colorless. Set in white metal, most people cannot see color in G or H stones face-up.
What does eye-clean mean?
That no inclusions are visible to the unaided eye at normal viewing distance. Many VS2 and some SI1 diamonds are eye-clean, but it must be checked stone by stone.
Is GIA stricter than IGI?
Both are major independent labs. GIA is the reference for natural diamonds; IGI grades a large share of laboratory-grown diamonds. Compare stones graded by the same lab.
What does a carat measure?
Weight: one carat is 200 milligrams. Two stones of the same weight can face up at different sizes depending on cut proportions.