A guide to pearls

Introduction

Pearls hold a unique place in the history of jewellery. Unlike every other gem, they are born inside a living organism, and to form they need time, expertise and precise environmental conditions. Today the pearl is a contemporary material, chosen for its natural elegance, for its range of shapes and colours, and for its ability to suit different styles, from the most essential to the most sophisticated.

This guide offers a clear and ordered view of the world of pearls: how they are formed, by what criteria they are judged, and which are the main types used in jewellery.

How pearls are formed

The pearls used in jewellery are almost all cultured. A nucleus is placed inside the mollusc, which responds by coating it with exceedingly thin layers of mother-of-pearl. The process lasts several years and calls for constant control of the growing environment: water quality, temperature, daily care of the farms.

The result is an organic gem, whose quality depends both on natural factors and on the experience of those who follow every stage of its growth. Natural pearls remain the exception — the conch and the melo — which form by pure accident and escape cultivation.

The quality criteria of a pearl

The assessment of a pearl follows criteria shared across gemmology:

• Lustre – the light the surface sends back, and the sharpness with which it sends it back

• Orient – the iridescence that surfaces from beneath, produced by the light that passes through the layers of aragonite; it is a property distinct from lustre, and it belongs to colour

• Surface – the small natural characteristics a pearl carries; number, depth and position all count

• Shape – round, semi-round or irregular; “baroque” denotes a shape, and runs across every type of pearl

• Colour – the body colour and the overtone produced by the mollusc

• Size – measured in millimetres, it bears on rarity and on value

The balance between these elements determines the final quality of the pearl.

The main types of pearls

Four types are the most widely used in jewellery, and each has an area of origin of its own. Akoya pearls are cultured in Japan. Freshwater pearls come from China; the large-diameter Freshwater pearls are the ones the market calls Edison. White South Sea pearls grow in Australia. Tahitian pearls come from French Polynesia.

For a detailed comparison between the different types, a dedicated page is available: Types of pearls: differences and characteristics.

Pearls in contemporary jewellery

In today's jewellery the pearl is reinterpreted in a modern language. It has left the exclusive province of the formal occasion and now enters jewels conceived for the daytime as well, thanks to its versatility and to its ability to converse with precious metals, diamonds and contemporary volumes.

Pearls and Made in Italy jewellery

The Italian tradition in jewellery is distinguished by attention to detail, technical expertise and aesthetic sensibility. The selection of pearls follows gemmological criteria shared internationally; Italian craftsmanship then brings out every single element, respecting its shape, its colour and its proportions.