The Diamond and Gemstone Guide

Our long-form reference for stones, from the Four Cs to gemstone durability

Welcome

Where to Begin

This is the reference guide behind all the others. Where the ring guides tell you how to choose a ring, this one tells you how to choose the stone that goes in it.

It covers diamonds properly, the Four Cs without the jargon, shapes, natural against lab-grown and fancy colour, then moves through coloured gemstones one at a time, with honest advice on what each can take.

It is longer than the others and not meant to be read in one sitting. Use the index and take what you need.

Contents

22 Chapters

Read in order, or jump to whichever question you have.

Diamonds Explained

The four diamond routes, and how they differ. Read this chapter.

The Four Cs

Cut, colour, clarity and carat, and where to spend first. Read this chapter.

Diamond Shapes

Twelve shapes, and which flatter which hands. Read this chapter.

Natural & Lab-Grown

What is identical, what differs, and the honest view on value. Read this chapter.

Fancy Coloured Diamonds

Yellow, champagne, pink, black and salt-and-pepper. Read this chapter.

Lab-Grown Fancy Colour

Vivid colour at a fraction of the natural price. Read this chapter.

Diamond Alternatives

Moissanite and the rest, compared honestly. Read this chapter.

A World of Colour

Sapphire, ruby, emerald and the rest, stone by stone. Read this chapter.

Sapphire

Eleven colours at Mohs 9, and the best all-round stone. Read this chapter.

Ruby

Red corundum, and why fine ruby outcosts diamond. Read this chapter.

Emerald

An unmatched green, and the protection it needs. Read this chapter.

Aquamarine

Soft sea-blue beryl, clean and affordable at size. Read this chapter.

Tanzanite

Violet-blue, single-source, more delicate than it looks. Read this chapter.

Morganite

Peach-pink beryl, and the rose gold pairing. Read this chapter.

Opal & Fire Opal

Play-of-colour, and the care it genuinely requires. Read this chapter.

Other Gemstones

Spinel, garnet, tourmaline, topaz and six more. Read this chapter.

Gemstone Durability

Hardness is not toughness, and which stones survive. Read this chapter.

Gemstone Treatments

Heat, oiling, filling and diffusion explained. Read this chapter.

Certificates & Reports

What a report confirms, and the four things it cannot. Read this chapter.

Ethical Sourcing

Kimberley Process, traceability and recycled metals. Read this chapter.

Heirloom & Reused Stones

Resetting a family stone, and reusing old gold. Read this chapter.

Birthstones

Twelve months, with a hardier alternative for each. Read this chapter.

The Diamond and Gemstone Guide

The Diamond and Gemstone Guide

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