From iron to diamond: a history of the engagement ring

In 1477 Maximilian of Habsburg, the future emperor, married Mary of Burgundy, heiress to one of the richest duchies in Europe. According to a tradition told in a great many books on jewellery, he sent her a ring set with diamonds for their betrothal, a gesture said to have launched the fashion among the courts. The story should be treated with caution, since direct sources are few; but it is certain that between the fifteenth and sixteenth centuries the diamond began to be associated with the promise of marriage.

A rare and untameable stone

For most of European history diamonds came almost exclusively from India, especially from the deposits of the Golconda region. They were extremely rare and hard to work: the technique of faceting was refined only in the late Middle Ages, in the workshops of Venice, Bruges and Antwerp. Before then the stone was valued more for its hardness than for its brilliance, and its very Greek name, adamas, meant «untameable».

It was precisely this hardness that made it suitable to symbolise a bond meant to last. Ancient authors such as Pliny the Elder credited it with extraordinary virtues, and in medieval lapidaries the diamond was described as the stone of firmness and constancy. The nuptial use grew from these beliefs: a ring that nothing could scratch became the sign of a fidelity that nothing should break.

From the courts to the middle classes

In the Renaissance the betrothal rings of noble families were often complex works of goldsmithing, with enamels, inscriptions, clasped hands and hearts. The diamond sometimes appeared as a small natural point, left in its octahedral shape. Some English and French rings bore a motto engraved inside, a custom that enjoyed great popularity in the sixteenth and seventeenth centuries.

The situation changed with the discovery of new deposits. From the 1720s Brazilian diamonds from Minas Gerais joined those from India, and after 1860 the South African mines around Kimberley multiplied the supply on an impressive scale. The stone remained precious, but it was no longer the preserve of the courts: the nineteenth-century middle classes could afford rings with small brilliants, often mounted in flower settings or as solitaires.

The solitaire and advertising

The design we now think of as classic, the solitaire with the stone raised on slender prongs, spread at the end of the nineteenth century, when the high setting allowed light to pass more freely through the brilliant. From then on the single-diamond ring became almost a synonym for a marriage proposal, especially in the English-speaking world and then, little by little, across Europe.

In the twentieth century advertising stepped in to consolidate the custom. The De Beers consortium, which controlled much of world production, promoted from 1947 the famous slogan «A Diamond Is Forever», explicitly linking the stone to the idea of eternal love. It was a remarkably successful commercial campaign, turning an aristocratic habit into a mass custom, which later spread even to countries such as Japan, where it had not existed before.

The history of the engagement ring thus reveals two intertwined souls. On one side stands the ancient symbol of Roman iron and clasped hands, on the other the taste for a rare stone that geology, trade and advertising gradually made accessible. Every solitaire carries with it, unknowingly, centuries of this long story.