Diamond Guide
Everything you need to choose with confidence, from natural and lab grown diamonds to the 4Cs, shapes and settings.
Natural vs lab grown diamonds
Both are real diamonds, with the same chemical make-up, hardness and sparkle. The difference is where they're formed, and that shapes the price.
Formed in the earth
Created over billions of years deep underground, then mined, cut and polished. Each one is rare and naturally unique.
- Our typical colour
- H–I
- Our typical clarity
- I1
Grown above ground
Grown from a diamond seed using technology that recreates the conditions of the earth. You get a larger, higher-grade diamond for your budget.
- Our typical colour
- F
- Our typical clarity
- VS
Every product page lists the diamond type, colour, clarity and setting for that piece.
The 4Cs
Cut, colour, clarity and carat are the four qualities used to describe every diamond.
Cut
How well a diamond is shaped and faceted to reflect light. A good cut is what makes a diamond sparkle, so it matters more than any other C for how it looks when you wear it.
Colour
Graded from D (completely colourless) to Z (light yellow or brown). The less colour, the more a diamond shows off its sparkle.
Our lab grown diamonds are F (colourless). Our natural diamonds are H–I (near colourless), which looks bright white once set, especially in white gold.
Clarity
Almost every diamond has tiny natural marks called inclusions. Clarity grades how many there are and how visible they are.
VS inclusions can't be seen without magnification. I1 inclusions may be visible on close inspection, and are an affordable choice for the small diamonds used in everyday jewellery.
Carat
Carat (ct) measures weight, not size. Where a piece has more than one diamond, the carat weight shown is the total weight of all its diamonds. A pair of 0.50ct stud earrings has 0.25ct in each earring.
| Carat weight | Approx. diameter (round) |
|---|---|
| 0.10ct | 3.0mm |
| 0.25ct | 4.1mm |
| 0.50ct | 5.1mm |
| 0.75ct | 5.8mm |
| 1.00ct | 6.5mm |
| 1.50ct | 7.4mm |
| 2.00ct | 8.1mm |
Sizes are a guide for a single round diamond. Other shapes can look larger or smaller at the same weight.
Diamond shapes
Shape is the outline of the diamond. Choose the one that suits your style.
Diamond settings
The setting is how the diamond is held in the metal. You'll find it listed on each product page.
- ProngSmall metal claws hold the diamond, letting in plenty of light for maximum sparkle. Also called a claw setting.
- Micro prongTiny claws that hold small diamonds with very little visible metal, so the diamonds take centre stage.
- PressureThe diamond is held securely by the grip of the surrounding metal, with no visible claws for a clean, smooth look.
- PavéMany small diamonds set closely together, creating a continuous surface of sparkle.
- ChannelDiamonds sit in a row between two walls of metal. Smooth and snag-free, ideal for wedding bands.
- BezelA rim of metal wraps around the diamond. Modern, secure and great for everyday wear.
- IllusionDiamonds are set into polished, shaped metal that reflects light, making them appear larger.
Diamond vs cubic zirconia
Cubic zirconia (CZ) is a man-made crystal that looks like diamond but isn't one. It's used in many fashion jewellery pieces.
| Diamond | Cubic zirconia | |
|---|---|---|
| What it is | Pure carbon | Zirconium dioxide |
| Hardness | 10 (hardest natural material) | 8–8.5 |
| Over time | Keeps its sparkle for life | Can scratch and cloud with wear |
| Price | Investment piece | Affordable fashion option |
Hardness is measured on the Mohs scale from 1 to 10.
Caring for your diamonds
- CleanSoak in warm, soapy water, brush gently with a soft toothbrush, then rinse and dry with a lint-free cloth. For quick touch-ups on the go, use the Connoisseurs Diamond Dazzle Stik. For a deeper clean at home, try the Connoisseurs LaSONIC Diamond Dazzler.
- StoreKeep pieces separately in a soft pouch or lined box. Diamonds can scratch other jewellery.
- ProtectRemove jewellery for the gym, gardening, swimming and cleaning, and avoid chlorine and harsh chemicals.
- CheckLook over claws and settings every few months. If a diamond feels loose, stop wearing it and contact us.
Shop our full range of jewellery cleaners, and see our warranty information for cover details by brand.
Still have questions?
Our team is happy to help you choose. Contact us, read our FAQs or find your fit with our ring size guide.