The Diamond Codex
Every dimension of the diamond world, the 4Cs, grading, history, geology, trade, ethics, investment, famous stones, and more. Free, sourced, honest.
107 articles · 18 sections
No articles match your search. Try a different keyword.
A
The 4Cs
Cut, colour, clarity, carat, the universal grading system
Start here
The complete 4Cs guide
The full framework, how cut, colour, clarity and carat interact to determine value.
Cut: the most important C
Why cut determines brilliance, fire and scintillation, and what Excellent really means.
Colour: D to Z explained
The GIA D–Z scale, what each grade looks like, and which colour is right for your setting.
Clarity: FL to I3 explained
Every clarity grade defined, what inclusions look like, and when eye-clean is enough.
Carat weight and size
Why carat is weight not size, how face-up dimensions vary, and the magic weight premiums.
4Cs buying guide
Specific grade recommendations by budget, what to prioritise at every price point.
B
Grading laboratories
GIA, IGI, and the standards that matter
Most searched
GIA vs IGI: the honest comparison
Which lab to trust, when IGI is acceptable, and why the difference matters financially.
GIA explained
What every field on a GIA grading report means, including the fields most buyers skip.
IGI explained
IGI's grading methodology, its use for lab-grown, and how to read an IGI report.
How diamond grading works
The grading process inside a laboratory, from submission to certificate issue.
Grading controversies
Grade inflation, inconsistency between labs, and what the trade knows that buyers don't.
Grading lab directory
All major diamond grading laboratories globally, what each does and whom it serves.
C
Industry standards
CIBJO, ISO, and the international frameworks
Standards overview
Why international diamond standards exist and who enforces them.
CIBJO Diamond Blue Book
The World Jewellery Confederation's diamond standards, what they require and why they matter.
ISO 18323: consumer confidence
The international standard for diamond consumer confidence and what it covers.
ISO 24016: grading terminology
The ISO standard for harmonising diamond grading terminology internationally.
WDC System of Warranties
The conflict-free diamond warranty system, what the invoice declaration means.
D
India: buying and the trade
Mumbai, Surat, and the India buyer's guide
Essential for Indian buyers
Buying diamonds in India
The complete India buying guide, certified dealers, price ranges, what to ask.
Mumbai's diamond trade
The BDB, Zaveri Bazaar, and how Mumbai became a global diamond hub.
BIS hallmarking guide
India's BIS hallmarking for gold jewellery, what the marks mean and why they matter.
GST and import duties
How GST applies to diamond jewellery in India and the import duty structure.
E
Lab-grown diamonds
CVD, HPHT, price collapse, and the honest comparison
What is a lab-grown diamond?
The definitive explainer, what lab-grown diamonds are and aren't.
Most searched
Natural vs lab-grown: the comparison
Side-by-side comparison on every dimension buyers actually care about.
CVD process explained
How chemical vapour deposition grows diamonds, the science behind the most common method.
HPHT process explained
High pressure, high temperature growth, the older method and how it differs from CVD.
The lab-grown price collapse
Why lab-grown prices fell 80% since 2019 and where they're heading.
Lab-grown producer directory
The major CVD and HPHT lab-grown diamond producers globally.
F
Famous diamonds
The world's most extraordinary stones
Famous diamonds: full directory
Every major famous diamond with provenance, history, and current location.
The Koh-i-Noor
India's most famous diamond, 5,000 years of history, conquest and controversy.
The Hope Diamond
The world's most famous blue diamond, from India to Paris to the Smithsonian.
The Cullinan Diamond
The largest gem diamond ever found, 3,106 carats and its extraordinary legacy.
The Pink Star
$71.2 million at Sotheby's, the world's most expensive diamond at auction.
The Regent Diamond
From a Golconda slave to the French crown jewels, one of history's most remarkable journeys.
The Orlov Diamond
The Mughal rose-cut stone that became a gift to Catherine the Great.
The Sancy Diamond
One of the earliest diamonds in European royal history, and its turbulent five centuries.
G
History
From ancient India to De Beers to the modern market
Ancient India and Golconda
The first diamond civilisation, how India dominated the diamond world for 2,000 years.
Africa: the discovery that changed everything
The 1867 Kimberley discovery and the transformation of the diamond world.
Colonial trade and diamond routes
How diamonds moved through Portuguese, Dutch and British colonial networks.
The De Beers story
Cecil Rhodes to Anglo American, the full history of the company that controlled diamonds.
A Diamond is Forever
The 1947 campaign that invented the engagement ring tradition, and changed consumer culture globally.
The modern era
From De Beers' monopoly collapse to lab-grown disruption, the diamond industry since 1990.
H
Ethics and sourcing
Conflict diamonds, Kimberley, G7 Protocol
Blood diamonds: the full story
What conflict diamonds are, which wars they funded, and what changed after Kimberley.
The Kimberley Process
The international certification scheme, what it does, what it doesn't, and the ongoing debates.
The G7 Diamond Protocol
The 2024 sanctions on Russian diamonds, how the verification system works and its trade effects.
Blockchain and traceability
Whether blockchain can solve the diamond provenance problem, and what it actually delivers.
I
Mining
Every method, every major mine, every company
Types of diamond mining
Open pit, underground, alluvial, marine, each method explained with real examples.
Major mines of the world
Jwaneng, Orapa, Argyle, Mir, Ekati, every significant mine named and profiled.
Mining technology
XRT sorters, DMS drums, laser sorters, the machines behind modern diamond extraction.
How diamond mining works
From ore body discovery to rough diamond recovery, the complete mining process.
J
Cutting and polishing
From rough to brilliant, Surat and the world's cutting centres
The cutting process
How a rough diamond becomes a polished gem, every stage from cleaving to final polish.
Planning and scanning
How AI-assisted scanning determines the optimal cutting plan for every rough diamond.
The polishing process
Bruting, blocking, brillianteering, how each polishing stage creates a finished stone.
The Surat story
How Surat processes 90% of the world's diamonds, and the community behind it.
Diamond cutting centres of the world
Surat, Antwerp, Israel, New York, who cuts what and why.
History of diamond cutting
From the point cut to the modern brilliant, 600 years of cutting innovation.
K
Supply chain
From mine to retail, how diamonds move through the world
L
Diamond shapes
Every cut style, proportions, character, and who it suits
Diamond shapes: full guide
Every shape compared, visual character, who it suits, and buying considerations for each.
Round brilliant
The world's most popular shape, why 58 facets and 100 years of optimisation still win.
Oval diamond
Elongating, flattering, brilliant, and the bowtie effect to watch for.
Cushion cut
Romantic and soft-edged, the vintage shape that's now mainstream.
Emerald cut
The step-cut hall of mirrors, architectural, glamorous, unforgiving of lower clarity.
Pear diamond
Unique, elongating, eye-catching, the shape that makes fingers look longer.
Princess cut
The square brilliant, sharp corners, high fire, and corner protection considerations.
Radiant cut
Brilliant faceting in a rectangular shape, the most forgiving fancy cut.
Marquise diamond
The longest, most dramatic shape, maximum face-up area per carat.
Asscher cut
Art Deco in diamond form, the square step cut with an octagonal outline.
Heart diamond
The ultimate romantic shape, symmetry requirements and setting guidance.
M
Ring settings
Solitaire to halo, every setting style explained
Settings guide: all styles
Every major ring setting compared, how each looks, how each protects the stone.
Solitaire settings
The classic choice, prong counts, head styles, band profiles, and maintenance.
Halo settings
How a halo adds visual size, the double halo, and pavé halo maintenance.
Pavé settings
Micro-pavé, shared prong pavé, and the care requirements for small-stone settings.
Three-stone settings
Past, present, future, the symbolic setting and how to choose the side stones.
Bezel settings
Full and partial bezel, maximum protection for active wearers.
Vintage settings
Art Deco, Edwardian, Victorian, period styles and finding a specialist jeweller.
Tension settings
The floating diamond, how tension settings work and their security considerations.
N
Geology
Formation, kimberlites, and why diamonds exist at all
How diamonds form
3 billion years, 200km deep, 50,000 atmospheres, the geology of diamond formation.
Kimberlite pipes
The volcanic conduits that bring diamonds to the surface, and how geologists find them.
Alluvial deposits
Secondary diamond deposits, from river gravels to marine mining off Namibia.
Diamond vs graphite
Why the same carbon atom forms both the hardest and one of the softest natural materials.
O
Trade and supply chain
Rapaport, bourses, sights, and how the trade actually works
How the diamond trade works
Sightholders, DTC, polished dealers, the full structure of the global diamond supply chain.
Rapaport explained
The Rapaport Price List, how discounts work, and what Rap means for buyers.
Diamond bourse directory
The world's major diamond bourses, Antwerp, Mumbai BDB, Surat SDB, and how to access them.
Rough diamond tenders
How competitive tender sales work, Lucara's Clara platform, and what tender results signal.
P
Investment
The honest case for diamonds as an asset class
Diamonds as investment: honest assessment
Returns data, store-of-value case, and when diamonds make financial sense, honestly.
Diamond resale value
Why retail resale is 25–50% of purchase price, the maths explained, and best resale routes.
Fancy colour diamonds as investment
Pink, blue, red, green, Argyle's closure, supply constraints, and the collector market.
The diamond auction market
Christie's, Sotheby's and how major diamond auctions work, for buyers and sellers from India.
Q
Markets
Global demand, US, China, India, luxury brands, lab-grown
The global diamond market
$80–85 billion at retail, size, trends, lab-grown disruption, and where the market is heading.
India's diamond consumer market
The wedding engine, organised retail transformation, Tier 2/3 growth, and the self-purchase rise.
The lab-grown diamond market
The CVD boom, Chinese producers, price collapse mechanics, and what comes next.
Luxury diamond brands
Cartier, Tiffany, Van Cleef, Bulgari, Harry Winston, Graff, what you pay for.
China's diamond market
The world's most uncertain major consumer, growth, slowdown, Gen-Z shift, and recovery question.
The US diamond market
50% of global demand, the engagement ring tradition, lab-grown disruption, and what's next.
R
Diamond jewellery
Beyond the ring, earrings, bracelets, metals, care
Diamond jewellery guide
Earrings, pendants, tennis bracelets, bangles, what to look for in every type.
Metals guide
Platinum vs white gold vs yellow vs rose gold, properties, maintenance, and India's 22kt problem.
Care and cleaning
How to clean at home, professional cleaning schedule, storage, and what actually damages diamonds.
S
Post-purchase
After you buy, insurance, upgrades, and travel
After you buy: the checklist
Verify the certificate, document it, insure it, five steps in the first week.
Diamond jewellery insurance
Household sub-limits, specialist insurance, premiums, and claims guidance for India.
Upgrades and modifications
Resetting, stone upgrades, halo conversions, and redesigning inherited rings.
Travelling with diamonds
Indian customs rules, TBE certificates, airport security, and insurance abroad.
T
Science and technology
Crystal structure, treatments, and detecting synthetics
The science of diamonds
Crystal structure, Type I and II classification, spectroscopy, and fluorescence.
HPHT colour treatment
How colour treatment works, GIA detection, disclosure, and whether treated diamonds are worth buying.
Clarity enhancement
Fracture filling and laser drilling, how they work, stability concerns, and GIA's policy.
Detecting synthetic diamonds
How lab-grown is identified by GIA, the melee mixing problem, and buyer protection.
U
Custom jewellery
Design, ethics, and bridal commissioning in India
Custom diamond ring design
Brief to finished piece, how the custom design process works, timeline, CAD, and costs in India.
Finding a designer in India
What credentials matter, questions to ask, red flags, and where to find skilled custom jewellers.
Ethical and sustainable custom jewellery
Recycled gold, Fairmined, Canada Mark, lab-grown, the honest sustainability picture for custom commissions.
Custom bridal jewellery
Engagement rings, wedding band coordination, Indian bridal suites, and wedding deadline planning.
V
Antique and vintage
Old mine cuts, Art Deco, Victorian, Edwardian, and estate buying
Guide to antique diamond cuts
Old mine cut, old European cut, rose cut — what makes each different and why collectors prize them.
Art Deco diamond jewellery
The 1920s period, geometric design, calibré cuts, platinum millegrain, and how to authenticate.
Victorian and Edwardian jewellery
Mourning jewellery, silver-topped gold, Edwardian platinum lace, and India's colonial connections.
Buying estate jewellery in India
Where to find period pieces, realistic prices, what to inspect, and red flags — a guide for Indian buyers.
Authenticating antique jewellery
Reading hallmarks, examining construction, identifying stone cuts, and spotting reproductions.
W
Men's diamonds
Rings, bracelets, pendants, gifting and watches
X
Diamond culture
Bollywood, Indian weddings, self-purchase and heirlooms
Y
Occasions
Engagement, anniversary, birthday, Diwali and milestone gifts
Most searched
Engagement ring buying guide
Budget, 4Cs priority, shape, setting, metal, sizing and where to buy in India.
Anniversary diamond guide
Anniversary milestones, eternity rings, engagement ring upgrades, and budget ideas by year.
Birthday, Diwali and milestone gifts
What to give at every budget and relationship — birthdays, Diwali, career milestones and more.
Z
Glossary
Every diamond term, A to Z, with search