What to Know Before You Choose a Diamond
Diamonds are among the most significant purchases most people will ever make, and the most emotionally loaded. Yet the information available to buyers is often either oversimplified ("just look for the biggest stone you can afford") or so technically complex it becomes paralysing. Sara's approach is different: practical, transparent, and grounded in 20 years of gemmological experience.
Here are the five things that genuinely matter when you're choosing a diamond, and the honest advice Sara gives every client who sits down with her in Kiama.
Cut: The Most Important Factor
Cut is how well the diamond's facets interact with light — and it has a greater impact on visual beauty than any other factor. A well-cut diamond will appear more brilliant, more fiery, and larger than a poorly cut stone of higher grades in every other category. Look for Excellent or Very Good cut grades. Never compromise on cut to chase a larger carat weight.
Sara's advice: Prioritise cut above all else. A smaller, well-cut stone will always outperform a larger, poorly cut one.Colour: Subtle Differences, Real Impact
Diamond colour is graded from D (completely colourless) to Z (light yellow or brown). The difference between adjacent grades is extremely subtle — and the premium between them is not. For most settings, G–H colour is the sweet spot: near-colourless to the naked eye, significantly more affordable than D–F, and virtually indistinguishable once set. In yellow or rose gold settings, you can often go lower still (I–J) without any visible warmth.
Sara's advice: G–H in white gold or platinum. I–J is fine in yellow or rose gold settings.Clarity: Inclusions Are Natural, Not a Flaw
Every diamond contains internal characteristics called inclusions — traces of the conditions under which it formed deep within the earth over billions of years. They are not defects; they are the stone's fingerprint. What matters is whether they are visible to the naked eye. An eye-clean SI1 or VS2 stone will look identical to a flawless stone in a ring setting — and cost considerably less. Reserve higher clarity grades for step-cut stones (emerald, Asscher), where the large open facets make inclusions more visible.
Sara's advice: Eye-clean SI1 is excellent value in round and pear cuts. Step cuts benefit from VS2 or higher.Carat: Size Isn't Everything
Carat is a measure of weight, not size — a poorly proportioned stone can weigh more than a well-cut stone of the same visual diameter. Choosing a stone that falls just below a carat threshold (0.90ct rather than 1.00ct, for example) can save significantly with no visible difference to anyone looking at the ring. Carat should be the last factor you optimise, not the first.
Sara's advice: Consider "magic sizes" minus a fraction — 0.90ct, 1.45ct, 1.90ct — for significant savings.Certification: The Factor Most Buyers Miss
A diamond certificate is an independent, objective assessment of the stone's characteristics by a trained gemmologist. It is the only way to verify what you are paying for. GIA (Gemological Institute of America) certification is the global gold standard — their grading is consistent, reproducible, and internationally recognised. Always request a GIA certificate before purchasing any significant diamond. Without it, you are taking the seller's word for every grade they quote.
Sara's advice: Only buy a GIA-certified diamond for any significant purchase. Every stone Sara offers is certified.
Left: Cut and clarity are assessed under magnification, but what matters most is what the stone looks like to the naked eye. Right: GIA certification provides objective, verifiable assurance of every quality grade.
Want help choosing a diamond? Sara provides transparent, pressure-free guidance and offers only GIA-certified stones for significant purchases.
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A bespoke white gold halo diamond ring from Sara's Kiama studio — every stone selected personally for its cut quality and GIA grading.
