FRESHWATER PEARL JEWELLERY: THE COMPLETE GUIDE

A pearl is the only gem made by an animal. Every other stone in a jewellery box was formed by pressure and heat and time inside the earth, then cut and polished by someone with a wheel. A pearl arrives finished. It was built slowly, in the dark, by a living creature responding to an irritation, and the surface you see is the surface it grew. Nothing was carved away to reveal it.

That single fact explains almost everything else about pearls: why no two are identical, why they are softer than they look, why they behave badly around perfume, and why they have never quite fitted the rules that jewellery usually obeys. This guide sets out what freshwater pearls are, how to judge one, what you are really buying when a pearl sits on a golden chain, and how to wear the result without any of the ceremony the twentieth century attached to it.

What A Pearl Is Made Of

Inside an oyster or a freshwater mussel there is a layer of tissue called the mantle, and its job is to build shell. When something lodges where it should not be, the mantle treats the intruder the way it treats the inside of the shell: it coats it. What it secretes is nacre, microscopic platelets of aragonite bound together by conchiolin, an organic protein. Layer settles over layer, thousands of them, for months or for years.

Nacre is the reason a pearl looks lit from within rather than shiny on the outside. Light enters the translucent layers, scatters between them and comes back out carrying depth and a faint iridescence. A glass bead painted to look like a pearl can be very bright, but the brightness sits on the surface like a coat of paint, and the difference is obvious once you have seen the two together.

It also explains the fragility. Nacre is organic and porous, which is why it sits at around two and a half on the hardness scale, softer than a copper coin. A pearl does not scratch the way a diamond refuses to. It dulls, slowly, when it meets acid, alcohol or oil, and it rewards being wiped rather than polished.

Sofia Godinho

Freshwater, Akoya, Tahitian, South Sea

Almost every pearl sold anywhere in the world today is cultured, which means a farmer gave the mollusc a reason to start rather than waiting for chance. Cultured is a method, not a grade, and it is not the opposite of real. The opposite of real is imitation, a bead of glass or plastic with a lacquer sprayed onto it. We go through the distinction properly in are freshwater pearls real pearls, because it is the question that causes the most confusion and costs people the most money.

Freshwater pearls grow in mussels, in lakes and rivers, and they are grown from a graft of mantle tissue rather than around an inserted bead. That has one consequence worth understanding: they are solid nacre the whole way through. There is no core underneath that can eventually show. It also means they grow into whatever shape the pocket of tissue allows, which is why irregularity is the norm and roundness the exception.

Akoya pearls come from a small saltwater oyster, mostly in Japan, and they are grown around a polished shell bead. The oyster coats it for under two years, leaving a nacre layer thinner than half a millimetre. The result is near perfect roundness and a cool, sharp lustre, closer to a mirror than to satin. Tahitian pearls come from the black-lipped oyster and carry natural greys, greens and aubergines. South Sea pearls, from a much larger oyster, are the biggest and the most expensive of the four.

None of this is a hierarchy of authenticity. It is a hierarchy of scarcity, and scarcity is a different thing from quality. A freshwater pearl with deep lustre and thick nacre is a better object than a thin, chalky Akoya, whatever the two cost.

Round, Baroque, Keshi: The Shape Question

The pearl trade built its entire grading system around roundness, for a practical reason: roundness is rare, easy to measure and easy to match. Sorting a harvest until you have fifty pearls identical in size, shape, colour and lustre is enormously laborious, and that labour is most of what a classic strand costs.

Baroque pearls sit outside that system by definition. They are not round, they cannot be matched, and so they are priced well below their symmetrical siblings while being made of exactly the same substance, often more of it. What you give up is conformity. What you get is a piece nobody else owns in that precise form. The full case is in what are baroque pearls, and a piece like the Mallorca Pearls Necklace is built entirely on that logic.

Within baroque there is a vocabulary worth knowing. Nugget pearls are compact and faintly irregular, the gentlest way in. Coin pearls are flattened discs. Drop and pear shapes hang with a natural weight that suits earrings. Keshi pearls formed with no nucleus at all, usually as a by-product when an implanted bead is rejected, and they tend to be small, flat and unusually luminous because they are solid nacre through and through.

How To Judge A Pearl

Four things decide whether a pearl is good, and they matter in this order.

Lustre comes first and is worth more than everything else combined. Hold the pearl near a window and look at how it returns the light. A good pearl gives you a reflection with a defined edge, almost a small bright shape you could describe. A poor one gives a vague white blur. Lustre is a direct read on how thick and well ordered the nacre is, which is why it predicts how the pearl will age better than any other measure.

Surface comes second. Small ridges, faint banding and the occasional tiny mark are normal and are in fact evidence that the pearl is real. What you are looking for is nothing deep enough to catch a fingernail, and nothing clustered where the pearl will face outward.

Nacre thickness comes third, and it is the reason freshwater pearls wear so well. A bead-nucleated pearl with a thin coat can eventually go through to the bead. A solid nacre pearl cannot, because there is nothing underneath to reach.

Matching comes last, and only matters if you want it to. In a strand of identical pearls it is most of the price. In a piece like the Elizabeth Pearls Necklace, where the pearls are meant to read as a group rather than as clones, it matters much less.

The Piece You Are Actually Buying

Here is the part that almost no pearl guide covers, and it is the one that matters most in practice. A pearl on a chain is two materials sharing one object, and they have opposite enemies.

Nacre fears chemistry. Perfume, hairspray, sunscreen, alcohol, anything acidic. It is largely indifferent to being rubbed by skin or silk. A golden finish achieved through 24K gold plating is the reverse: it does not mind a splash of clean water, but it minds friction, and it minds the salt and acid in sweat sitting against it for hours. Which is why a bracelet ages faster than a pair of earrings on the same wrist and the same day, and why the pieces that live against warm skin take the hardest life.

The consequence is that the advice written for heirloom pearls, the one that says never water and never perfume, is only half an answer for the object you actually own. We wrote the honest, summer-calibrated version in can you wear pearls in the water.

The short version: pearls at the beach yes, pearls in the water no. Jewellery on last, after sunscreen and perfume, off first, before the shower. A soft dry cloth at the end of the day. Never put anything away damp. That is genuinely most of it.

How To Wear Them Now

Pearls spent most of the twentieth century acquiring rules, and the rules aged badly while the pearl did not. The uniform strand, the matching set, the twinset, the occasion. A piece kept in a box for weddings will always look like the past when it comes out, because it has no ordinary life to belong to.

Four small changes undo all of it. Choose one piece instead of a set. Prefer an irregular shape to a uniform one. Mix pearls with golden pieces rather than keeping them apart, which is the fastest way to break the formal spell: a pearl against warm golden metal loses its bridal quality entirely. And wear them in daylight, with ordinary clothes, on an ordinary day. A pair of Pearly Earrings with a white shirt reads as considered without reading as dressed up, which is the whole trick.

None of that is our invention. It is what the runways and the fashion press have been arguing for several seasons, and we set out the evidence in are pearls in style, from Chanel's oversized pearls to the one placement the fashion press now considers finished.

The styling in detail is in the modern way to wear pearls, and if the question underneath yours is really about permission rather than proportion, we took that one apart in what age should you wear pearls. The answer, briefly, is that there is no age. There are only contexts, and contexts are made rather than inherited.

Living With Them

Pearls reward being worn often and handled gently, which is a rare combination and a pleasant one. The habits are small enough to become automatic. Put them on last. Take them off first. Wipe them with a soft cloth before they go away. Store them apart from harder pieces, ideally in a pouch, and never in a sealed box while damp. If a strand is old and knotted on silk, look at the thread rather than the pearls, because the thread is what fails.

The full method is in our guide to caring for your jewellery, and the pearls themselves, including the baroque pieces, the drops and the everyday studs, are in the pearl collection. Beside them sits Reflections, the collection they were designed to be layered with.

A pearl was made by something alive, slowly, and it will show the life you give it. Worn twice a year it stays perfect and means nothing. Worn constantly it softens, and it becomes yours. That trade is the entire argument for buying one, and it is the thread running through every one of the nine moments that made the pearl.