Guides for buyers, jewellers and dealers
Practical, plainly-written guides on buying loose diamonds, sourcing gemstones direct, using live dealer feeds, pricing strategy, and the cert labs and markets that matter.
Start with the guides written for you
Chaos has guides for different audiences. Pick the path closest to what you are trying to do, then move into the deeper topic library below.
I want to buy or source a stone
Start with certificates, price comparison, availability and the difference between dealer supply and retail jewellery sales.
I want live stones for client work
Learn how to browse dealer stock, quote clients, use markups, and connect live inventory into your own sales workflow.
I want to list inventory on Chaos
Understand approval, API feeds, WhatsApp intake and the details that help jewellers trust your stock quickly.
Diamond and gemstone cut reference
One authoritative page per meaningful cut — round brilliant to Old Mine and Old European antique cuts — connected to live availability, related cuts and buying guidance.
Browse the Cut Library →Diamond fundamentals
The 4Cs of Diamonds Explained: Cut, Colour, Clarity, Carat
What cut, colour, clarity and carat actually measure, which one matters most for sparkle, and how to prioritise a budget across all four.
Lab-Grown vs Natural Diamonds: What Buyers Need to Know
Chemically identical, priced worlds apart. How lab-grown and natural diamonds compare on origin, certification, value retention and what matters when buying.
GIA vs IGI: Diamond Certification Differences Explained
GIA and IGI grade diamonds on the same 4Cs scale but differ on strictness, lab-grown reporting and price — what the difference actually means for buyers.
Diamond Shape Guide: Which Cut Is Right for You?
Round, oval, cushion, emerald, princess or something rarer — how to choose a diamond shape by budget, hand shape and how much sparkle you want.
Fancy Colour Diamonds: Yellow, Pink, Blue & Black Diamond Guide
Fancy colour diamonds are graded on a different scale to colourless diamonds — how hue, tone and intensity drive value, and why saturation is what matters most.
How to buy a loose diamond online without getting lost
A plain-English guide for retail buyers comparing certified loose diamonds by shape, lab, carat, colour, clarity and availability.
Diamond certificates explained for buyers
What GIA, IGI and other diamond reports do, what they do not do, and which certificate details to check before enquiry.
Origin Report vs Identification Report: What's the Difference?
An identification report confirms what a stone is. An origin report goes further — and not every lab, or every stone, can support one.
How to source an engagement ring diamond
How to turn a ring idea into a diamond sourcing brief that Chaos, a jeweller or a dealer can actually fulfil.
Diamond shape & size
Oval Diamond Buying Guide: Ratio, Bow-Tie & Price
What length-to-width ratio to look for, how to judge the bow-tie effect, and how oval compares on price to round — a practical buying guide.
Elongated Cushion Cut Diamond Buying Guide
One of 2026's defining engagement ring shapes — the ratio to look for, how it compares to oval, and why it often costs less per carat.
Emerald Cut Diamond Buying Guide: Clarity, Budget & Ratio
Why emerald cut needs a cleaner clarity grade than brilliant shapes, and why it typically costs meaningfully less per carat than round.
Marquise Diamond Buying Guide: Ratio, Points & Bow-Tie
The ratio most buyers prefer, why the pointed tips need a protective setting, and how to judge the bow-tie effect on a marquise.
Old Mine Cut Diamond Buying Guide: Rarity & Price
Genuinely rare, no longer produced, and increasingly hard to find untouched — what drives Old Mine Cut prices and where to actually buy one.
1 Carat vs 1.5 Carat Diamond: Size, Price & Look Compared
A 1.5ct round diamond is only around 12% wider than a 1ct, not 50% bigger — what actually changes in size, price and everyday look.
1.5 Carat vs 2 Carat Diamond: Size, Price & Look Compared
A 2ct round diamond covers roughly 50% of an average finger's width versus 45% at 1.5ct — a genuinely noticeable step up, at a real price jump.
Which Diamond Shape Looks Biggest for Its Carat Weight?
Elongated shapes spread more surface area across the finger than round does for the same carat weight — which ones give you the most visible size.
Diamond Carat Size Chart: Millimetres by Shape and Weight
Reference dimensions for round, oval and emerald cut diamonds at 1ct, 1.5ct and 2ct — a quick way to check whether a specific stone has good spread.
Oval vs Round Diamond: Price, Sparkle & Size Compared
Round has more concentrated sparkle and better durability; oval typically costs less per carat and looks larger. How to choose between them.
Oval vs Elongated Cushion Diamond Compared
A continuous curve versus a rounded-square outline stretched long — how oval and elongated cushion actually differ, and how to choose.
Emerald Cut vs Radiant Cut Diamond Compared
Step-cut mirrors versus brilliant-cut sparkle on a similar rectangular outline — the real difference between emerald and radiant cut.
Old Mine Cut vs Old European Cut Diamond Compared
A softer, cushion-shaped hand-cut stone versus its rounder, more symmetrical successor — the real history and visual difference explained.
Marquise vs Oval Diamond Compared
Two elongated shapes that both look bigger than their carat weight — the difference in outline, durability and how each wears in a setting.
The Bow-Tie Effect Explained: Which Shapes Show It
A dark shadow across the centre of an oval, marquise, pear or elongated cushion isn't always a flaw — how to tell a good bow-tie from a bad one.
Diamond Windowing and Extinction Explained
Two different ways a poorly cut diamond fails to sparkle — windowing lets light pass straight through, extinction traps it without returning it.
Crushed Ice vs Faceted Diamonds: What's the Difference?
Crushed ice isn't a flaw — it's a deliberate faceting style with its own distinct sparkle. How to tell whether it's the look you actually want.
Diamond Spread Explained: Why Same-Carat Stones Look Different Sizes
Two diamonds of identical carat weight can look meaningfully different in size face-up — spread is why, and it's something you can actually check for.
Milky and Cloudy Diamonds Explained
A hazy, washed-out look that a certificate's clarity grade alone won't warn you about — what causes it and how to check before you buy.
Diamond Inclusions Explained: Feathers, Cavities & Eye-Clean
What a feather inclusion, a cavity, and "eye-clean" clarity actually mean — and which inclusion types are cosmetic versus genuinely worth avoiding.
Diamond Fluorescence: Is It Good or Bad?
Neither, on its own — fluorescence can make a lower colour grade look whiter, or make a high-colour stone look hazy. What actually determines which.
Diamond Table, Depth & Culet Explained
Three proportion terms that together determine how well a diamond returns light — what the percentages mean and what to look for.
Is it worth it?
Is D Colour Worth It? Diamond Colour Grade Explained
The visible difference between D, E and F is barely perceptible even to a trained eye — where your money is usually better spent instead.
Is VVS Clarity Worth It? Diamond Clarity Grade Explained
VVS, VS and most SI1 diamonds all look equally clean to the naked eye — where the real "eye-clean" threshold sits, and what the premium actually buys.
Is GIA Certification Worth It?
Yes, for anything beyond a token purchase — what a GIA report actually protects, and why it matters most at resale.
Is an Old Mine Cut Diamond Worth Buying?
You're paying a real rarity premium over a modern cut of similar size and quality — what that premium buys, and who it's genuinely worth it for.
Lab-grown diamonds
CVD vs HPHT Lab-Grown Diamonds: What's the Difference?
The two processes used to grow diamonds in a lab produce real diamonds by different routes — and the difference shows up in typical colour, clarity and price.
Can Jewellers Tell If a Diamond Is Lab-Grown?
Not by eye, and not with a loupe — lab-grown and natural diamonds are optically identical. What actually detects the difference, and why a report beats an opinion.
Do Lab-Grown Diamonds Hold Their Value?
No — and it's structural, not incidental. Why lab-grown diamond prices have kept falling since large-scale production began, and what that means for resale.
Lab-Grown Diamond Certification: What to Check on the Report
GIA stopped full 4Cs grading on lab-grown diamonds in October 2025; IGI still does. What that split means, and exactly what to check before you buy.
Is a Lab-Grown Diamond Worth It?
It depends entirely on what you're optimising for: size and clarity per budget, or resale value and geological rarity. A straight framework for deciding.
Antique diamond cuts
Antique Diamond Cuts Explained: A Buyer's Overview
Old Mine, Old European, Rose Cut and Transitional — four distinct antique faceting styles, what era each comes from, and how to choose between them.
Rose Cut Diamond Buying Guide: History, Look & What to Check
No pavilion, no brilliant sparkle by design — a flat-based, domed antique cut with a softer glimmer. What defines it, and what to check before buying.
Transitional Cut Diamond Explained
Cut mostly in the 1930s-40s, bridging Old European Cut and the modern round brilliant — more sparkle than Old European, more period character than modern.
Where to Buy Antique Cut Diamonds (and What to Check)
Genuine antique cuts come almost entirely from estates, auctions and specialist antique dealers — not new production. What to check before you buy one.
Are Antique Cut Diamonds a Good Investment?
Antique cuts carry a genuinely different value story than natural or lab-grown modern diamonds — fixed, shrinking supply rather than ongoing production.
Fancy colour diamonds
Yellow Diamond Buying Guide: The Accessible Fancy Colour
The most affordable fancy colour diamond by a wide margin, and a genuinely good value entry point into coloured diamonds. What to look for.
Pink Diamond Buying Guide: Rarity After Argyle
The Argyle mine, once the source of the vast majority of the world's pink diamonds, closed for good in 2020. What that means for price and sourcing today.
Blue Diamond Buying Guide: Rarity, Origin & the Hope Diamond
Natural blue diamonds owe their colour to trace boron and are dominated by a single mine. What makes them rare, and what to check before buying one.
Are Treated Colour Diamonds Worth Buying?
Irradiation and HPHT treatment produce vivid colour at a fraction of natural fancy colour pricing — a different purchase, not a bargain version of the same thing.
Fancy Colour Diamond Certification: What to Check
Colour grading a fancy diamond is genuinely specialised, and the single most important line on the report is whether colour origin is natural or treated.
Coloured gemstones
How to source a certified sapphire
A buyer-focused sapphire sourcing guide covering colour, origin, treatment, lab reports and what to ask before quote.
Sapphire vs Diamond Engagement Ring: Which to Choose
Sapphire is the closest like-for-like swap for diamond — nearly as hard, genuinely daily-wear durable, and typically a fraction of the cost per carat.
Sapphire Engagement Ring Buying Guide: Origin & Colour
Kashmir, Burma and Ceylon sapphires each have a genuinely different look and price tier. What "cornflower" and "royal blue" actually mean, and what to buy.
Ruby Buying Guide: Pigeon Blood, Origin & Treatment
"Pigeon blood" is a specific, lab-awarded colour term, not marketing — what it means, how Burmese and Mozambique rubies differ, and what treatment does to price.
Emerald Buying Guide: Oiling, Origin & Durability
Oiling is standard on the vast majority of emeralds and isn't a flaw — but the degree matters enormously to price. What to check, and how to wear one safely.
Alexandrite Buying Guide: Colour Change, Rarity & Price
Green in daylight, red under incandescent light — genuine natural alexandrite with a strong colour shift is rarer than a flawless large diamond.
Spinel Buying Guide: The Great Impostor
For centuries, spinel was mistaken for ruby in Europe's crown jewels — including the Black Prince's Ruby itself. Now it's a connoisseur's choice in its own right.
Tanzanite Buying Guide: Found Nowhere Else on Earth
Every piece of tanzanite in existence comes from one hillside in Tanzania. A trichroic stone that shows blue, violet and burgundy depending on the angle.
Paraiba Tourmaline Buying Guide: The Neon Gemstone
Copper is what gives Paraiba tourmaline its electric neon glow. Brazilian material commands a steep premium over the newer African deposits — here's why.
Moissanite vs Diamond: Fire, Durability & Price Compared
A lab-created diamond simulant, not a diamond substitute — more fire, nearly as hard, and a small fraction of the price. What genuinely differs, and what doesn't.
How to Choose a Coloured Gemstone for an Engagement Ring
Sapphire, ruby, emerald, alexandrite, spinel, tanzanite, Paraiba tourmaline and moissanite — a decision framework for choosing between them.
Buying for yourself
Buying Yourself a Diamond: A Practical Guide
Self-purchase is a real and growing share of the diamond market. What's different about buying for yourself versus buying (or being bought) an engagement ring.
Right-Hand Ring Diamond Buying Guide
No engagement-ring conventions to follow — a right-hand ring can take a bolder shape, setting or stone than most buyers would choose for a wedding ring.
Diamond Eternity Band Buying Guide: Full vs Half
Full eternity carries roughly double the diamonds (and cost) of half eternity, and can't be resized. What actually differs, and how to choose.
Diamond Stud Earrings Buying Guide
Total carat weight means both earrings combined, not each — a "1 carat pair" is usually 0.50ct per ear. What to check for a genuinely matched pair.
How Much Should You Spend on a Diamond for Yourself?
There's no "X months' salary" rule for self-purchase, and the engagement-ring version of that rule is worth ignoring too. A more useful way to set a budget.
Bespoke sourcing
Buying a Loose Diamond for a Bespoke Engagement Ring
Find the diamond you love first, then have a jeweller design around it — a practical guide to sourcing your own stone before you choose a setting.
Should You Buy the Diamond or the Ring First?
The order most buyers default to isn't the only one — why choosing your stone before your setting often gets you a better result.
Can You Take Your Own Diamond to a Jeweller?
Yes — most bespoke and custom jewellers routinely set client-supplied stones. What to check before you do, and what to bring with you.
How to Choose a Diamond Before Choosing a Ring Setting
Shape, carat, budget and certification — the decisions to make about the stone itself before a setting even enters the conversation.
Trade & the gem business
Wholesale vs retail: how the gem trade actually prices
Why one dealer's 'wholesale' is another's retail, and how Chaos forces transparent dealer pricing across the platform.
How Gemstones Are Priced: Colour, Clarity, Cut, Carat, Origin & Treatment
Coloured gemstones aren't priced like diamonds — colour usually matters more than clarity, and origin and treatment can swing value more than either.
Ethical & Conflict-Free Gemstone Sourcing: A Buyer's Guide
What the Kimberley Process actually covers (and doesn't), how coloured-stone traceability differs from diamonds, and what to ask before you buy.
Where Do Diamonds and Gemstones Come From?
The major diamond and coloured-gemstone producing countries, how origin is determined, and why it increasingly matters as much as the 4Cs.
Markup strategy for independent jewellers
How to apply a sensible wholesale-to-retail markup per stone type, dealer and currency without scaring off clients.
GIA, IGI, Gübelin and SSEF — which cert lab to trust
A buyer's tour of the gemstone certification labs that matter, what each is strict on, and when a cert is worth the wait.
Gemstone Treatments Explained: Heat, Oil, Diffusion & More
What heat treatment, oiling, fracture-filling, diffusion and irradiation actually do, which are standard and accepted, and which should always change the price.
How to source coloured gemstones direct from cutters
A practical playbook for buying sapphires, rubies and emeralds direct from verified dealers in Jaipur, Bangkok and Colombo — skipping the broker chain.
Jaipur, Bangkok, Colombo — the world's gem cutting hubs
What each market specialises in, how dealers price, and how to evaluate offers from each region remotely.
How to Sell Gemstones Wholesale Online: A Dealer's Guide
What serious trade buyers actually look for in a wholesale listing — photography, disclosure, pricing transparency — and how to build a channel that repeats.
Dealer Listing Photography Guide: Shooting Stones That Sell
A trade buyer sourcing sight-unseen prices risk into every listing with weak photography. What equipment and shots actually reduce that risk.
How to Write Stone Listings That Sell
Trade buyers scan for specific facts in a specific order. What a listing description needs to include, and the vague language that costs you enquiries.
Wholesale Pricing Strategy for Dealers
Underpricing to move stock and overpricing to protect margin both cost you the same way: buyers stop trusting your price list. A better approach.
Responding to Enquiries Fast: A Dealer's Guide
Response time is one of the strongest trust signals a buyer sees before ever meeting you. What "fast" actually means, and how to protect it at scale.
Building Dealer Trust and Credibility on Chaos
Verification badges and review history reduce a buyer's perceived risk before they ever message you. What actually earns that trust, and keeps it.
What Jewellers Actually Search For (and How to Stock It)
The questions buyers ask before they ever contact a dealer reveal exactly what to stock and how to describe it. A dealer's view of Chaos's own buyer research.
International Shipping and Payment Terms for Gemstone Dealers
Loose stones are flatly prohibited by some major carriers, and payment terms in the gem trade run differently to most B2B goods. What to actually use.
Finding Your Dealer Niche
Competing directly on round diamonds means competing on price alone. A defined niche — antique cuts, fancy colour, a specific coloured stone — competes on expertise.
Using Buyer Demand Signals to Decide What to Stock
Chaos's Wanted page shows aggregated, anonymised buyer demand in real time — a live signal for what to actually source next, not a guess.
Common Dealer Mistakes That Lose Sales
Most lost sales trace back to a handful of repeated, avoidable mistakes — not bad stones or bad luck. A closing checklist across the whole dealer cluster.
Embedding a live gemstone feed on your jewellery website
Show your customers a constantly-refreshed catalogue from the dealers you trust — works on Shopify, Wix, Webflow, Squarespace, WordPress or any custom build.
Birthstones by Month: The Complete Guide
The modern and traditional birthstone for every month, why some months have more than one option, and what to look for when buying each.
Mohs Hardness Scale: Which Gemstones Are Safe for Everyday Wear
What the Mohs scale actually measures, why hardness alone doesn't equal durability, and which gemstones hold up to daily wear in a ring.
Non-Diamond Engagement Rings: Sapphire, Ruby, Emerald & Moissanite
Sapphire, ruby, emerald and moissanite are the four realistic diamond alternatives for an everyday engagement ring — how they compare on durability, cost and look.
How to Clean and Care for Gemstone Jewellery Safely
Which gemstones tolerate an ultrasonic cleaner, which never should, and the safe warm-water method that works for almost everything.
Padparadscha Sapphire: Colour, Rarity & Buying Guide
The rarest named sapphire colour — what defines the pink-orange "lotus" hue, why even top labs disagree on classifying it, and what drives its price.
Anniversary Gemstones by Year: The Complete Guide
The traditional gemstone assigned to each wedding anniversary milestone, from the 5th (sapphire) to the 60th (diamond) — and why some stones repeat.
Precious vs Semi-Precious Gemstones: Why the Split Is Outdated
Diamond, ruby, sapphire and emerald were labelled "precious" in the 1800s for reasons that have little to do with value today — what actually determines worth.
How to Get Gemstone Jewellery Appraised and Insured
What a jewellery appraisal actually covers, how to find a qualified appraiser, what it costs, and how appraised value differs from what you paid.
Asterism Explained: Star Sapphires and Star Rubies
What causes the six-rayed star inside a star sapphire or star ruby, why it only shows on a cabochon cut, and what to look for when buying one.
Chatoyancy Explained: Cat's Eye Gemstones
The moving band of light across a cabochon-cut cat's eye stone, why chrysoberyl shows it best of all, and what "cat's eye" means without a species name attached.
Ring Settings Guide: Prong, Bezel, Halo & Pavé Explained
How prong, bezel, halo, pavé, channel and tension settings differ in security, stone protection and everyday-wear practicality.
How to Spot a Fake or Synthetic Gemstone
Simple at-home checks — inclusions, the fog test, weight, heat conductivity — and where they stop working, plus what actually distinguishes synthetic from simulant.
Opal Guide: Play-of-Colour, Types & Buying Considerations
What causes opal's shifting play-of-colour, how black, white, boulder and fire opal differ, and why durability — not just colour — should drive your choice.
Blue Gemstones Guide: Sapphire, Tanzanite, Aquamarine & Topaz
Four blue stones, four very different price points and durability profiles — how to choose between sapphire, tanzanite, aquamarine and blue topaz.
Green Gemstones Guide: Emerald, Peridot, Tsavorite & Tourmaline
Emerald isn't the only green stone worth considering — how peridot, tsavorite garnet and green tourmaline compare on price, durability and colour.
Gold vs Platinum vs Silver: Choosing a Metal for Your Setting
Karat purity, durability and upkeep compared across yellow/white/rose gold, platinum and silver — and how metal choice interacts with your stone.
Vintage & Antique Jewellery Buying Guide: Eras Explained
How to tell Georgian, Victorian, Edwardian, Art Deco and Retro jewellery apart, and what to check before buying a piece described as antique.
Gemstone Meanings and Symbolism: A History Guide
What ruby, sapphire, emerald, amethyst and other gemstones have traditionally symbolised across history and culture — folklore and heritage, not medical claims.
Yellow & Pink Gemstones Guide: Citrine, Morganite & More
Warm-toned alternatives to the classics — citrine, yellow sapphire, morganite and pink tourmaline compared on price, durability and colour.
For jewellers
How to Price Setting-Only Work for Client-Supplied Stones
No stone margin to absorb overhead and risk, so setting-only pricing needs its own logic — not just your normal labour rate with the stone cost removed.
What to Check Before Setting a Client-Supplied Diamond
A consistent intake checklist protects you as much as the client — verify the stone against its certificate, document condition, and get it in writing.
Insurance and Liability for Client-Supplied Stones
Standard jewellers block insurance doesn't automatically cover a client's property. Bailee's coverage is the specific policy line that does — check yours.
Talking Clients Through the Client-Supplied Stone Process
A client who's sourced their own stone is usually more engaged and better-informed than average — set expectations early and the relationship runs smoother.
Building a Client-Sourced-Stone Service Into Your Business
More buyers are sourcing their own stone before ever meeting a jeweller. Being genuinely set up to work with them well is a real, differentiating offer.
More guides
Buying a Diamond for an Engagement Ring: Where to Start
The reading order that actually matters — six decisions, in sequence, each with the deeper guide linked.
Which of the 4Cs Matters Most When Buying a Diamond?
Cut, colour, clarity and carat don't carry equal weight — a practical order for where to spend your budget.
How to Find Her Ring Size Without Her Knowing
Practical, low-risk ways to get an accurate ring size for a surprise proposal — and what to do if you guess wrong.
Which Diamond Shape Suits Your Hand?
Finger length, hand size and nail shape all change how a diamond shape reads — a practical styling guide, not a rule.
Buying a Coloured Gemstone for an Engagement Ring: Where to Start
The reading order for choosing a coloured stone engagement ring — colour, durability, treatment and origin, in the sequence that matters.
What Determines a Coloured Gemstone's Quality?
Coloured stones aren't graded like diamonds — colour usually leads, clarity expectations vary by species, and origin can matter more than either.
Tsavorite Garnet Buying Guide: Colour, Rarity & No-Treatment Value
Why GIA distinguishes tsavorite from demantoid, what drives its price, and why it rarely needs a treatment disclosure at all.
Heated vs Unheated Sapphire: What the Treatment Actually Changes
Heat treatment is standard, disclosed, and shapes price more than almost any other single factor in sapphire buying.
Ruby vs Spinel: How to Tell Them Apart (And Why It Matters)
Two red stones, one long history of confusion — some of the world's most famous "rubies" are actually spinel.
Colombian vs Zambian Emerald: Origin, Colour & Price
Colombian carries the historic premium; Zambian often delivers comparable — sometimes better — clarity for less. Neither is the "wrong" choice.
How UK Wholesale Diamond & Gemstone Buying Actually Works
Hatton Garden, the London Diamond Bourse, and the tax mechanics that make loose stones different from most goods — a practical map, not a legal opinion.
Wholesale buying guides by stone type
Properties, what to look for, certification guidance, treatment standards and typical wholesale price tiers — for every major coloured stone and diamond category.