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Harlow Mercantile
Education

Know your stone.

Plain-language guides to lab-grown diamonds, gemstones, IGI certification, and choosing a stone you’ll love for a lifetime.

Start here · 6 min

Lab-Grown vs Natural Diamonds

Chemically, optically, and physically identical, with a different origin story.

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Lab-grown diamonds are grown in a laboratory using the same crystal structure and chemistry as mined diamonds. They are graded by the same independent laboratories on the same 4Cs: cut, color, clarity, and carat weight. Optically, they are indistinguishable.

What changes is the origin: no mining, no supply-chain guesswork, and a smaller environmental footprint.

6 min

Lab-Grown Diamonds vs Moissanite

Two different stones, side by side: composition, brilliance, hardness, and price.

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5 min

Understanding Diamond Clarity

From Flawless to Included: how to read a clarity grade and what it means for the eye.

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5 min

The Diamond Colour Guide

D through Z, and where the human eye actually starts to notice.

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7 min

Diamond Shapes, Explained

Round, oval, cushion, emerald, pear, marquise, and how each wears on the hand.

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6 min

IGI Certification, Explained

What an IGI report actually verifies, and how to read one line by line.

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6 min

How to Buy Confidently from the Vault

How the Vault philosophy, IGI certification, and honest photography help you buy with confidence.

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6 min

How to Choose the Perfect Center Stone

A short, honest framework for picking a stone you'll love for a lifetime.

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6 min

What Makes Lab-Grown Gemstones Different?

Sapphires, rubies, and emeralds grown in the lab: same crystal, cleaner origin.

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7 min

A Guide to Custom Fine Jewelry

How to think about commissioning a piece around a Harlow stone.

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Questions about a stone, a comparison, or a future custom piece all go to a real person.

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