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LILY DIA

Diamond Buying Guide

This comprehensive diamond buying guide explains how to evaluate and choose diamonds using the 4Cs grading system (Cut, Colour, Clarity, Carat), diamond certification reports, and shape selection. Learn the differences between lab-grown diamonds and natural diamonds, including pricing, optical properties, and grading standards.

Whether selecting a centre stone for an engagement ring or comparing certified diamonds, this guide covers diamond quality factors, grading report interpretation, and how cut grade impacts brilliance and sparkle. Start with diamond shape selection, then evaluate colour grade and clarity grade based on your metal choice and size preferences.

How to choose a diamond

A lab-grown diamond is the same material as a mined diamond, but origin changes price, availability and what the purchase means to you. Once origin is clear, shape and cut usually matter more than chasing the highest grades on paper.

Lab-grown diamonds

  1. #01

    Lab-grown diamonds Australia

    How lab-grown diamonds are made, graded and compared with mined diamonds.

  2. #02

    Are lab-grown diamonds real?

    The short answer on chemistry, hardness, grading reports and everyday wear.

  3. #03

    Are lab-grown diamonds worth it?

    Where lab-grown diamonds offer value, and where resale, rarity and budget still matter.

  4. #04

    Lab-grown vs natural diamonds

    Compare origin, price, grading, appearance and what changes once the stone is set.

The 4Cs

  1. #01

    The 4Cs of diamonds

    Cut, colour, clarity and carat weight explained in the order buyers should judge them.

  2. #02

    Diamond clarity chart

    Compare clarity grades and learn when inclusions are likely to be visible.

  3. #03

    Diamond colour chart

    See how D to Z colour grades read in yellow gold, white gold, platinum and rose gold.

Diamond certification, ethics and alternatives

  1. #01

    Diamond certification and GIA reports

    How to read GIA and IGI reports before comparing natural or lab-grown diamonds.

  2. #02

    Ethical diamonds

    What ethical sourcing means, what lab-grown changes and what buyers should still ask.

  3. #03

    Moissanite vs diamond

    Compare sparkle, hardness, price and long-term expectations across two popular stones.

Diamond shapes

  1. #01

    Round brilliant cut

    The most familiar diamond shape, with strong brightness and easy comparison.

  2. #02

    Oval cut

    A lengthening shape that needs careful attention to bow tie, ratio and symmetry.

  3. #03

    Emerald cut

    A step cut where clarity, colour and proportion are easier to see at a glance.

  4. #04

    Cushion cut

    Soft corners, varied facet styles and a shape that changes a lot from stone to stone.

  5. #05

    Marquise cut

    A long pointed shape that looks larger for its carat weight and needs protected tips.

  6. #06

    Pear shaped

    A teardrop shape where the point, shoulders and bow tie decide how balanced it looks.

  7. #07

    Princess cut

    A square brilliant shape with crisp corners and a modern, structured look.

  8. #08

    Radiant cut

    A brilliant rectangular or square cut that combines sparkle with sharper geometry.

  9. #09

    Asscher cut

    A square step cut with cropped corners and a deep, mirrored hall of mirrors look.

  10. #10

    Old mine cut

    An antique cushion-shaped cut with a soft, candlelit glow and genuine history.