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MOH

Unit G.4 Ground Floor, Treasure House

19-21 Hatton Garden

London EC1N 8BA

+44 (0) 7586 775867care@mohlondon.com

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MyOtherHalf
Collection of brilliant-cut diamonds
  1. Guidance
  2. Diamond Guide

Diamond Guide

Buying a diamond is one of the most considered purchases you will make. Our experts have written these guides to give you the knowledge to choose with confidence — whether you are selecting a stone in Hatton Garden or browsing online.

C

Colour

D to Z grading scale

C

Cut

Light return & brilliance

C

Clarity

Inclusions & blemishes

C

Carat

Weight & apparent size

All Diamond Guides

Diamond Anatomy

Diamond Anatomy

Table, crown, girdle, pavilion — learn the parts that define brilliance.

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Diamond Colour

Diamond Colour

From colourless D to the faint yellow Z — the GIA scale explained in plain terms.

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The Cut

The Cut

The most important of the 4Cs. Cut determines how a diamond returns light to your eye.

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Clarity Grades

Clarity Grades

Flawless to I3 — understanding inclusions and what actually matters to your eye.

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Carat Weight

Carat Weight

Size versus weight — why a well-cut 0.90ct can face-up larger than a 1.00ct.

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Certification

Certification

GIA, IGI, HRD — what each laboratory grades, and why certification matters for resale.

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Fluorescence

Fluorescence

Does fluorescence help or hurt? The honest answer — including when it can save you money.

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Fancy Colour Diamonds

Fancy Colour Diamonds

Yellow, pink, blue — how coloured diamonds are graded and priced differently.

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Diamond Sizes

Diamond Sizes

Visual size guides across carat weights and shapes — see it before you buy.

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Ethically Sourced

Ethically Sourced

Kimberley Process, lab-grown, and our own sourcing standards at MOH London.

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Diamond Shapes

Diamond Shapes

Round, oval, princess, cushion and more — each shape has its own character.

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Ready to choose your diamond?

Search our live inventory or book a consultation with a specialist.

Start with a DiamondBook a Consultation