A buyer's guide to evaluating a gemstone
The four Cs, adapted for coloured stones.
Colour comes first
For coloured stones, colour accounts for roughly 60% of value. Hue (the colour itself), tone (light to dark), and saturation (pure to greyish) are the three axes. The most prized colours sit at peak saturation, medium-to-dark tone, and a specific hue ideal for the species — pigeon-blood red for ruby, royal blue for sapphire, vivid green for emerald.
Two stones of identical carat weight can trade at a 10x price difference based purely on colour. This is where to spend.
Cut is the most underrated attribute
A poorly cut stone leaks light through the bottom (a "window") and looks dim regardless of colour quality. A well-cut stone reflects light from every facet and looks alive on the skin. Cut quality is not on most certificates and must be evaluated in person or by trusted photography under controlled light. We will always show a stone in motion before quoting.
Carat is third
Per-carat price scales non-linearly. A 2-carat ruby of equivalent quality can cost 4-6x a 1-carat ruby because larger rough is exponentially rarer. Below 1ct, per-carat prices flatten; above 3ct, they accelerate. Buy the size your design genuinely needs — not the largest you can afford.
Clarity last — within reason
For coloured stones, clarity matters only insofar as it affects durability and transparency. An emerald with significant surface-reaching fractures is fragile. A ruby with cloud inclusions can look milky. Beyond those concerns, eye-clean is enough.
Spend order, in descending priority: Colour → Cut → Carat → Clarity. Reverse this only for diamonds.