S for Spinel

In its red variety, this stone was long confused with the ruby and embellished many historic jewellery sets. Unjustly forgotten, it is now making a comeback on the jewellery scene.

In the world of gems, spinel has been dogged by its reputation as an impostor, particularly when it has a fine red shade, like the ruby. It was found in the great royal courts from Great Britain to Russia under misleading names like the Black Prince’s Ruby, Tamburlaine’s Ruby and Catherine the Great’s Ruby. The first, a 170 ct cabochon named after one of its illustrious owners, Edward of Woodstock (1330-1376), has adorned the heads of several British sovereigns and features in the current imperial crown; the second, an engraved stone weighing over 350 ct, is at the center of a necklace created in 1853 for Queen Victoria; the third, weighing 398 ct, was set in the crown of the Russian empress, Catherine II, in 1762. In France, old inventories also list “three rubies” among the crown jewels, which turned out to be spinels. These were the “A Romain” (over 120 ct), the Œuf de Naples (241 ct) and the famous Côte de Bretagne. Originally belonging to Anne de Bretagne and then to her daughter Claude de France, who passed it on to her husband François I, this gem weighed 206 ct, but was recut in 1750 in the form of a 107 ct dragon to decorate Louis XV’s insignia of the Golden Fleece. It was not realised until the very early 19th century that the world’s largest rubies were actually spinels. Before mineralogy became a science, stones were classified according to their colour. At that time, the reds formed a single large family and were called “carbuncles” (from the Latin carbunculus, meaning a small burning coal).
 

Balas or “Balais Rubies”

In the Middle Ages, another generic term came into use: “ruby” (from the Latin ruber, meaning red). To describe the shades generally associated with their provenance, dark red stones were called “Bohemian” rubies and light red ones “Balas” or “Balais” rubies. While the former were garnets, the latter were spinels, extracted for the most part from the Kuh-i-Lal mines in the Badakhshan region, formerly known as Balascia and now lying in Northeastern Afghanistan, on the border with Tajikistan. Although the spinel was first described in Europe in 1546 by the scholar Georg Bauer, it was not until 1783 that it was officially distinguished from the ruby. Advances in chemistry and the advent of crystallography under Jean-Baptiste Louis Romé de L’Isle led to the realization that the two stones belonged to different mineral species. Assumed to derive its name from the Latin spina, meaning “thorn” (because of its pointed crystals), spinel now forms a species in its own right, which contains stones in a variety of colours (blue, gray, violet, etc.) depending on the impurities present in its crystalline structure. When colored red by chromium, this aluminium and magnesium oxide has good hardness (8 out of 10 on the Mohs scale) and fine brilliance, and with large carat weights also has the advantage of much clearer transparency than that of its exquisite rival, the ruby. As witness the largest of these specimens, owned by the Crown of Iran and known as the Samarian Spinel, which weighs around 500 ct.

The Spinel: A Symbol of Power

In addition to its rarity in the mineral world, the reason that red was so predominant in this large family of stones was its symbolic power. In the West, red evoked the blood of Christ, as well as fire, ardour and might, and was associated with power. In medieval times, spinels were even the pride of various royal treasuries and featured prominently on the insignia of sovereigns, starting with their crowns. Some of these stones were marked by the peregrinations of world history, the most famous example undoubtedly being the Black Prince’s Ruby. This jewel reached England in the late 14th century, having passed from the Moorish king of Granada’s hands to those of Peter the Cruel of Castile, who gave it to Edward of Woodstock in 1367 as a reward for his military aid. Legend has it that in 1415 it saved the life of Henry V, who wore it during the Battle of Agincourt, when it protected him from a deadly spear. Much prized in the West, red spinel was equally admired in the East and in the Islamic world, where it was identified much earlier, in the 11th century, as different from the ruby by the Persian scholar Al-Beruni. In India, with the Great Mughals, the gem was even classified in the highest category of precious stones, according to a description of their treasure by the historian Abu’l Fazl at the end of the 16th century (see the article by Marie-Laure Cassius-Duranton, Technè review No. 54, 2022). Protective talismans and symbols of imperial power handed down from generation to generation, the finest red spinels were engraved with the names and titles of their illustrious owners, as with the Carew spinel, now in the Victoria & Albert Museum in London. This 133 ct stone is engraved with the names of three great emperors: Jahangir, Shah Jahan (who built the Taj Mahal) and Alamgir (known in the West as Aurangzeb). Similarly, the misleadingly named Tamburlaine Ruby, which probably never belonged to Tamburlaine, is also engraved with the names of five great Mughal rulers. But these rulers also liked to wear these polished stones in the form of large, oblong beads mounted on long necklaces.

A Comeback on the Market

Although the spinel enjoyed a glorious past, it was ousted by the ruby and from the 19th century onwards became a second-rank stone in the West. This trend was undoubtedly reinforced by the rise in popularity of diamonds, which, when cut to a fine shape, finally supplanted red gems as the royal stone. Today, however, after two centuries of disfavour, the spinel seems to be taking its revenge and is emerging as a worthy alternative to the ruby, which has become extremely expensive. Mined in Tajikistan, Myanmar and Sri Lanka, as well as in Vietnam and Tanzania, the spinel is used in refined jewellery creations – in its red version, of course, and sometimes in other shades like cobalt blue, hot pink or grey. Particularly appreciated by professionals, who recognise its gemmological qualities, this stone is also prized because no treatment can alter it, since heating or irradiating it barely touches its appearance. In the auction world, where only red spinels really attract attention, some exceptional pieces have also whetted buyers’ appetites in recent years. In 2011, for instance, Christie’s sold an imperial necklace of the Great Mughals, containing gems totalling 1,131.59 ct, for CHF4.5 M (around €3.6 M at today’s value), after estimates of between CHF1.4 M and CHF 2.4 M. In 2015, a pendant brooch with a 50 ct centre stone that belonged to the famous banker Henry Philip Hope (owner of the blue diamond that bears his name) fetched £962,000 (around €2 M) at Bonhams in London. Almost 100 years earlier, in 1917, this same spinel was sold for £1,060 (the equivalent of £80,000 in 2015, or €107,000). Confirming this return to favour, last year Christie’s sold a ring set with a 20.8 ct Tanzanian stone for CHF882,000 (around €930,000), bringing the price per carat to CHF42,400 (€44,710). While spinel is attracting growing international interest, particularly in the high-end market, in France it is finding it harder to emerge from the ruby’s shadow and is still rare and unobtrusive at auction. A situation that sounds like an appeal to lovers of fine stones.