The legendary aura of pearls dates back to an era before the stones were cultured artificially. Before pearls began to be cultured commercially in Japan at the beginning of the 20th century, pearl divers along the warm coasts off India, Ceylon (Sri Lanka) and the Arabian Peninsula had had to open countless closed mussels – an incredible physical effort – to find naturally-grown pearls, known as “Oriental pearls”, purely by chance. Today, Oriental pearls found in this way would be almost priceless. Appropriately costly, often even more expensive than most precious stones, these natural pearls had enormous symbolic character.

Tradition has it that Indian and Chinese rulers laid their feet on sumptuous carpets of pearls – an idea later taken up by the Maharajah of Baroda when he commissioned a lavish carpet of pearls in 2009, later auctioned for USD 5 million. Eventually pearls also made it to Egypt, Greece, Rome and Byzantium, either on trading routes or as the booty of war, where they were considered impressive status symbols. Emperor Caligula scored points with his pearl-inlaid slippers, for instance, while the ladies of Rome liked to have the interiors of their carriages lined with the stones.

Mentioned in the Book of Revelations, pearls acquired an increasingly religious character from the Middle Ages onwards, as they began to be viewed as an allegory for the love of God. This mindset inspired the Spanish Conquistadors of the 16th century to process the pearl treasures captured from the temples of the Aztecs into artful beneficences back in Europe. Examples include the Cloak of the Madonna in Toledo Cathedral, which is inlaid with 80,000 pearls. Even secular noblewomen such as Maria de Medici, wife of Henry IV of France, liked to dress in lavish, pearl-encrusted robes, however. Legend has it that she owned a dress decorated with over 3,000 diamonds and 32,000 pearls. Due to the incredible weight of the dress, however, she could hardly walk when wearing it, prompting derision amongst her critics at the French court. The greatest such extravagance to be recorded in modern times was in 1908, when the last Empress of China was buried together with a sumptuous pearl blanket. Regrettably, this was later plundered in the throes of the country’s revolution.

There are a range of decisive criteria for evaluating the quality of pearls, as well as the question of whether they are freshwater, cultured saltwater or even the immeasurably expensive, natural Oriental versions of the stones. These criteria include the stones’ lustre, also referred to as their enamel, the quality of their surface, their size, form, colour, and the thickness of the mother-of-pearl. Freshwater pearls have a weaker lustre, and are rarely round. In the case of cultured saltwater pearls, a distinction is drawn between Akoya, Tahitian and South Sea pearls, depending on their origin. Originally from Japan, Akoya pearls are now also cultured in China and Vietnam, and feature the thinnest layer of mother-of-pearl out of the three types of cultured pearl. Tahitian pearls, made famous in Europe by Kaiserin Eugenie above all, are captivating thanks to their dark colouring, which ranges from grey, silver or black, through blue-green, to the nuanced green-pink colour known as “peacock”. The white, silver-tinted and gold-yellow South Sea pearls, which occur in Indonesia, Australia and the Philippines, are the most opulent of all cultured pearls, reaching an impressive size of up to 20 mm.