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The four Cs, explained
Understand cut, colour, clarity and carat before comparing individual diamonds.
Cut: how the light returns
Facet arrangement and proportions influence brightness and flashes of colour. Shape is the outline—round, oval or pear—not a cut-quality grade. GIA’s standard cut grade covers round brilliant diamonds in the D-to-Z colour range; do not assume every shape carries that grade.
Colour: a scale with a specific scope
The D-to-Z scale describes increasing yellow or brown tint, beginning with colourless D. Fancy-colour diamonds use a different assessment. Compare the actual stone rather than judging its grade from a screen.
Clarity: details inside and on the surface
Inclusions and blemishes affect clarity. Their size, location and other characteristics matter; a grade is not simply a count of marks. Compare the report with the diamond’s appearance.
Carat: weight rather than width
One carat equals 0.2 grams. Equal-weight diamonds may have different dimensions. Ask whether the listed weight describes the centre diamond or all diamonds combined.
Before you decide
Questions to ask before you buy
- Which report belongs to this diamond?
- What are its measurements and disclosed treatments?
- Which details change with my selected product option?
Sources & further reading
Check each product page for exact specifications, or ask us if anything is unclear.
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