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CHAOS
Learning Hub

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.

Choose your path

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.

Retail buyers

I want to buy or source a stone

Start with certificates, price comparison, availability and the difference between dealer supply and retail jewellery sales.

Jewellers

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.

Dealers

I want to list inventory on Chaos

Understand approval, API feeds, WhatsApp intake and the details that help jewellers trust your stock quickly.

Cut Library

Diamond and gemstone cut reference

One authoritative page per meaningful cut β€” round brilliant to Old Mine and Old European antique cuts β€” connected to live availability, related cuts and buying guidance.

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Tools

Diamond size visualiser

Compare round, oval and emerald-cut diamonds side by side at 1, 1.5 and 2 carats β€” a to-scale visual companion to our diamond carat size chart.

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Diamond shape & size

Shape buying guides

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 β€” a practical buying guide.

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Shape buying guides

Elongated Cushion Cut Diamond Buying Guide

One of 2026's defining engagement ring shapes β€” the ratio to look for, how it compares to oval, and why it often costs less per carat.

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Shape buying guides

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.

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Shape buying guides

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.

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Shape buying guides

Old Mine Cut Diamond Buying Guide: Rarity & Price

Genuinely rare, no longer produced, and increasingly hard to find untouched β€” what drives Old Mine Cut prices and where to actually buy one.

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Shape buying guides

Which Diamond Shape Suits Your Hand?

Finger length, hand size and nail shape all change how a diamond shape reads β€” a practical styling guide, not a rule.

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Diamond size

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 β€” what actually changes in size, price and everyday look.

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Diamond size

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 β€” a genuinely noticeable step up, at a real price jump.

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Diamond size

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 β€” which ones give you the most visible size.

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Diamond 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 β€” a quick way to check whether a specific stone has good spread.

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Compare

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.

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Compare

Oval vs Elongated Cushion Diamond Compared

A continuous curve versus a rounded-square outline stretched long β€” how oval and elongated cushion actually differ, and how to choose.

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Compare

Emerald Cut vs Radiant Cut Diamond Compared

Step-cut mirrors versus brilliant-cut sparkle on a similar rectangular outline β€” the real difference between emerald and radiant cut.

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Compare

Old Mine Cut vs Old European Cut Diamond Compared

A softer, cushion-shaped hand-cut stone versus its rounder, more symmetrical successor β€” the real history and visual difference explained.

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Compare

Marquise vs Oval Diamond Compared

Two elongated shapes that both look bigger than their carat weight β€” the difference in outline, durability and how each wears in a setting.

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Diamond problems

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 β€” how to tell a good bow-tie from a bad one.

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Diamond problems

Diamond Windowing and Extinction Explained

Two different ways a poorly cut diamond fails to sparkle β€” windowing lets light pass straight through, extinction traps it without returning it.

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Diamond problems

Crushed Ice vs Faceted Diamonds: What's the Difference?

Crushed ice isn't a flaw β€” it's a deliberate faceting style with its own distinct sparkle. How to tell whether it's the look you actually want.

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Diamond problems

Diamond Spread Explained: Why Same-Carat Stones Look Different Sizes

Two diamonds of identical carat weight can look meaningfully different in size face-up β€” spread is why, and it's something you can actually check for.

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Diamond problems

Milky and Cloudy Diamonds Explained

A hazy, washed-out look that a certificate's clarity grade alone won't warn you about β€” what causes it and how to check before you buy.

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Diamond problems

Diamond Inclusions Explained: Feathers, Cavities & Eye-Clean

What a feather inclusion, a cavity, and "eye-clean" clarity actually mean β€” and which inclusion types are cosmetic versus genuinely worth avoiding.

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Diamond problems

Diamond Fluorescence: Is It Good or Bad?

Neither, on its own β€” fluorescence can make a lower colour grade look whiter, or make a high-colour stone look hazy. What actually determines which.

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Diamond problems

Diamond Table, Depth & Culet Explained

Three proportion terms that together determine how well a diamond returns light β€” what the percentages mean and what to look for.

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Coloured gemstones

Coloured stones

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 β€” skipping the broker chain.

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Coloured stones

How to source a certified sapphire

A buyer-focused sapphire sourcing guide covering colour, origin, treatment, lab reports and what to ask before quote.

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Coloured stones

Sapphire vs Diamond Engagement Ring: Which to Choose

Sapphire is the closest like-for-like swap for diamond β€” nearly as hard, genuinely daily-wear durable, and typically a fraction of the cost per carat.

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Coloured stones

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.

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Coloured stones

Ruby Buying Guide: Pigeon Blood, Origin & Treatment

"Pigeon blood" is a specific, lab-awarded colour term, not marketing β€” what it means, how Burmese and Mozambique rubies differ, and what treatment does to price.

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Coloured stones

Emerald Buying Guide: Oiling, Origin & Durability

Oiling is standard on the vast majority of emeralds and isn't a flaw β€” but the degree matters enormously to price. What to check, and how to wear one safely.

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Coloured stones

Alexandrite Buying Guide: Colour Change, Rarity & Price

Green in daylight, red under incandescent light β€” genuine natural alexandrite with a strong colour shift is rarer than a flawless large diamond.

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Coloured stones

Spinel Buying Guide: The Great Impostor

For centuries, spinel was mistaken for ruby in Europe's crown jewels β€” including the Black Prince's Ruby itself. Now it's a connoisseur's choice in its own right.

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Coloured stones

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.

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Coloured stones

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 β€” here's why.

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Coloured stones

Moissanite vs Diamond: Fire, Durability & Price Compared

A lab-created diamond simulant, not a diamond substitute β€” more fire, nearly as hard, and a small fraction of the price. What genuinely differs, and what doesn't.

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Coloured stones

How to Choose a Coloured Gemstone for an Engagement Ring

Sapphire, ruby, emerald, alexandrite, spinel, tanzanite, Paraiba tourmaline and moissanite β€” a decision framework for choosing between them.

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Coloured stones

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.

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Coloured stones

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.

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Coloured stones

Ruby vs Spinel: How to Tell Them Apart (And Why It Matters)

Two red stones, one long history of confusion β€” some of the world's most famous "rubies" are actually spinel.

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Coloured stones

Colombian vs Zambian Emerald: Origin, Colour & Price

Colombian carries the historic premium; Zambian often delivers comparable β€” sometimes better β€” clarity for less. Neither is the "wrong" choice.

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Coloured stones

Origin Report vs Identification Report: What's the Difference?

An identification report confirms what a stone is. An origin report goes further β€” and not every lab, or every stone, can support one.

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Coloured stones

Tourmaline Buying Guide: Colour Varieties, Watermelon & Liddicoatite

Tourmaline has the widest colour range of any gem species β€” a map of its named varieties, what watermelon zoning actually is, and what to expect on clarity by colour.

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Coloured stones

Aquamarine Buying Guide: Why Origin Matters Less Than You'd Think

GIA's own FAQ corrects two common assumptions about aquamarine: "Santa Maria" no longer reliably means Brazilian, and origin isn't what actually drives the stone's value.

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Trade & the gem business

Trade

Jaipur, Bangkok, Colombo β€” the world's gem cutting hubs

What each market specialises in, how dealers price, and how to evaluate offers from each region remotely.

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Trade

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.

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Trade

How Gemstones Are Priced: Colour, Clarity, Cut, Carat, Origin & Treatment

Coloured gemstones aren't priced like diamonds β€” colour usually matters more than clarity, and origin and treatment can swing value more than either.

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Trade

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.

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Trade

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.

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Trade

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 β€” a practical map, not a legal opinion.

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Trade

How Wholesale Diamond & Gemstone Buying Works in the US: A Jeweller's Guide

No federal VAT, resale certificates, Form 8300 cash reporting, and why most loose diamonds clear US customs duty-free -- the US-specific mechanics behind wholesale trade.

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Trade

How Wholesale Diamond & Gemstone Buying Works in the UAE: A Jeweller's Guide

Dubai's reverse-charge VAT mechanism for precious stones, the DMCC free zone, and what changed in 2025 -- the UAE-specific mechanics behind wholesale trade.

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Trade

How Wholesale Diamond & Gemstone Buying Works in India: A Jeweller's Guide

Surat's cutting houses, Mumbai's Bharat Diamond Bourse, GST rates by stage, and why hallmarking doesn't apply to loose stones -- the India-specific trade mechanics.

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Trade

How Wholesale Diamond & Gemstone Buying Works in Hong Kong: A Jeweller's Guide

Why Hong Kong has no sales tax, no import duty, and a Kimberley Process registration system for rough stones -- the trade mechanics behind Asia's diamond hub.

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Quality

GIA, IGI, GΓΌbelin and SSEF β€” 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.

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Quality

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.

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Quality

What Determines a Coloured Gemstone's Quality?

Coloured stones aren't graded like diamonds β€” colour usually leads, clarity expectations vary by species, and origin can matter more than either.

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For dealers

How to Sell Gemstones Wholesale Online: A Dealer's Guide

What serious trade buyers actually look for in a wholesale listing β€” photography, disclosure, pricing transparency β€” and how to build a channel that repeats.

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For dealers

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.

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For dealers

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.

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For dealers

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.

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For dealers

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.

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For dealers

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.

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For dealers

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.

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For dealers

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.

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For dealers

Finding Your Dealer Niche

Competing directly on round diamonds means competing on price alone. A defined niche β€” antique cuts, fancy colour, a specific coloured stone β€” competes on expertise.

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For dealers

Using Buyer Demand Signals to Decide What to Stock

Chaos's Wanted page shows aggregated, anonymised buyer demand in real time β€” a live signal for what to actually source next, not a guess.

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For dealers

Common Dealer Mistakes That Lose Sales

Most lost sales trace back to a handful of repeated, avoidable mistakes β€” not bad stones or bad luck. A closing checklist across the whole dealer cluster.

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Buying guides

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.

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Buying guides

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.

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Buying guides

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.

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Buying guides

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.

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Buying guides

Non-Diamond Engagement Rings: Sapphire, Ruby, Emerald & Moissanite

Sapphire, ruby, emerald and moissanite are the four realistic diamond alternatives for an everyday engagement ring β€” how they compare on durability, cost and look.

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Buying guides

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.

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Buying guides

Padparadscha Sapphire: Colour, Rarity & Buying Guide

The rarest named sapphire colour β€” what defines the pink-orange "lotus" hue, why even top labs disagree on classifying it, and what drives its price.

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Buying guides

Anniversary Gemstones by Year: The Complete Guide

The traditional gemstone assigned to each wedding anniversary milestone, from the 5th (sapphire) to the 60th (diamond) β€” and why some stones repeat.

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Buying guides

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 β€” what actually determines worth.

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Buying guides

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.

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Buying guides

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.

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Buying guides

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.

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Buying guides

Ring Settings Guide: Prong, Bezel, Halo & PavΓ© Explained

How prong, bezel, halo, pavΓ©, channel and tension settings differ in security, stone protection and everyday-wear practicality.

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Buying guides

How to Spot a Fake or Synthetic Gemstone

Simple at-home checks β€” inclusions, the fog test, weight, heat conductivity β€” and where they stop working, plus what actually distinguishes synthetic from simulant.

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Buying guides

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 β€” not just colour β€” should drive your choice.

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Buying guides

Blue Gemstones Guide: Sapphire, Tanzanite, Aquamarine & Topaz

Four blue stones, four very different price points and durability profiles β€” how to choose between sapphire, tanzanite, aquamarine and blue topaz.

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Buying guides

Green Gemstones Guide: Emerald, Peridot, Tsavorite & Tourmaline

Emerald isn't the only green stone worth considering β€” how peridot, tsavorite garnet and green tourmaline compare on price, durability and colour.

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Buying guides

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 β€” and how metal choice interacts with your stone.

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Buying guides

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.

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Buying guides

Gemstone Meanings and Symbolism: A History Guide

What ruby, sapphire, emerald, amethyst and other gemstones have traditionally symbolised across history and culture β€” folklore and heritage, not medical claims.

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Buying guides

Yellow & Pink Gemstones Guide: Citrine, Morganite & More

Warm-toned alternatives to the classics β€” citrine, yellow sapphire, morganite and pink tourmaline compared on price, durability and colour.

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For jewellers

For jewellers

Embedding a live gemstone feed on your jewellery website

Show your customers a constantly-refreshed catalogue from the dealers you trust β€” works on Shopify, Wix, Webflow, Squarespace, WordPress or any custom build.

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For jewellers

Markup strategy for independent jewellers

How to apply a sensible wholesale-to-retail markup per stone type, dealer and currency without scaring off clients.

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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 β€” not just your normal labour rate with the stone cost removed.

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For jewellers

What to Check Before Setting a Client-Supplied Diamond

A consistent intake checklist protects you as much as the client β€” verify the stone against its certificate, document condition, and get it in writing.

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For jewellers

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 β€” check yours.

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For jewellers

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 β€” set expectations early and the relationship runs smoother.

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For jewellers

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.

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Gemstone Encyclopedia

Wholesale buying guides by stone type

Properties, what to look for, certification guidance, treatment standards and typical wholesale price tiers β€” for every major coloured stone and diamond category.