Pearl shopping has a problem that diamond shopping does not: there is no independent grading authority. No GIA certificate, no standard scale, no referee. Every seller grades their own pearls and writes their own definitions. That sounds hopeless, but it isn't — it just means you need to evaluate pearls yourself instead of trusting a letter grade. This guide teaches you how, in the order that matters.
1. Luster first — always
Luster is what makes a pearl look like a pearl instead of a white bead, and it is the first thing to check because it can't be faked and can't be fixed. The test is simple: look at the reflections on the pearl's surface.
- Good luster: reflections are sharp and defined. Hold the strand up and you can make out the outline of your own head in the surface. Light comes back at you.
- Poor luster: the surface looks milky, chalky, or diffuse. Light scatters instead of reflecting. No amount of size or roundness rescues a chalky pearl.
That outline-reflection test is the exact standard we grade against — it is the first criterion on our Quality & Value page. A lustrous 7 mm pearl is a better purchase than a chalky 9 mm one, every time.
2. Surface
Real pearls are grown by a living animal, and almost all of them carry some surface character — tiny ridges, pinpoints, or marks. The question is where and how much. Marks confined to the drill area disappear when the pearl is strung. Pitting, cracks, or spotting on the face that sits forward when worn do not. Ask to see photos in diffuse daylight, not studio glamour lighting — harsh lighting hides surface flaws in blown-out highlights.
3. Shape
"Round" should mean round. Off-round pearls sold as round are one of the most common corners cut in this industry. Our own tolerance is published: round and near-round strands are within 0.9 mm of true across the strand. Baroque and off-round pearls are beautiful when they are sold as what they are — the problem is only ever the mislabelling.
4. Matching
A strand is a set, and a set can fail even when every individual pearl passes. Look down the full length of the strand: the pearls should step evenly in size with consistent body colour and overtone from end to end. Visible size-stepping or colour drift between the two ends means the strand was assembled carelessly. Our matching tolerance is 0.9 mm across the strand.
5. Size — and honest measuring
Pearls are measured at their widest point in millimetres. The thing to watch for is rounding up: a 7.4 mm pearl sold as "8 mm" is a meaningful misstatement, because price scales steeply with size. We list to the nearest 0.5 mm. Not sure what the millimetre numbers actually look like? See our size guide.
6. Nacre
Ask one question: bead-nucleated or solid nacre? Most freshwater pearls are solid nacre throughout — no shell bead at the core, nothing to wear through. Bead-nucleated pearls are legitimate products (all akoya are bead-nucleated — see our freshwater vs. akoya comparison), but a bead-nucleated pearl represented as solid nacre is a misrepresentation.
How to shop when grades mean nothing
Since "AAA" means whatever each seller decides it means, do this instead:
- Ignore the letter grade. Read what the seller says the grade means. If they don't define it anywhere, that tells you something too.
- Ask for photos in diffuse, indirect light — the least flattering, most honest lighting.
- Check the return policy before the pearls. A seller confident in their grading gives you time to disagree. We give 60 days.
- Ask what they reject. A real standard produces rejects. Roughly 7 in 10 strands we are offered do not make it past our sorting.
Questions to ask any pearl seller
Use these on us. Use them on everyone else too — that's the point.
- What does your grade actually mean, criterion by criterion — and where is that published?
- Are these pearls solid nacre or bead-nucleated?
- Is the colour natural or treated?
- What is the exact size, and do you round up?
- Is the strand hand-knotted between pearls, or glued?
- What is your return window, and who pays return shipping?
When you're ready to put the checklist to work, browse our jewelry — every listing states size, grade, shape, and colour, and the grading scale behind them is public.