Owners of this stone ranged from the tenacious to the hapless, the romantic to the cunning. This diamond helped persuade a Queen to risk her fleet, a king to satisfy the love pangs of his son, another King to go into hock, a Duke to risk his wealth, an Italian turned Frenchman to covet it, and a nameless person to steal it. It changed names twice, from that of the country which initially possessed it to the name of its final recorded owner. Not seen in centuries, its beauty is lost to all but an anonymous owner. Such is the story of the Mirror of Portugal.

The story begins with the death of Cardinal King Henry, ruler of Portugal. Believing himself to be the successor to the throne is King Manual I’s illegitimate grandson, Dom António de Castro, Prior of Crato who declares himself António I. However, Portugal’s neighbor, Spain, sees things differently and refuses to recognize Dom António as Portugal’s new ruler preferring their own King Philip II (legitimate heir through a female line). Not taking the snub lightly, Dom António fights for his right to rule his country. When he and his army are defeated by Spain, Dom António escapes to Paris, taking with him a portion of the Portuguese Crown Jewels. One of these jewels is the prized Mirror of Portugal, described as a table-cut of approximately 30 carats. While in Paris, Dom António and his followers regroup and he tries once again to convince Spain that he should be the ruler of Portugal. But his efforts are again thwarted by his defeat in the battle for the Azores. Now twice defeated by Spain, Dom António nevertheless takes his “never say die” attitude – and his Portuguese Crown Jewels – and escapes to England.

Now in London, Dom António attempts to sell the jewels to the British Crown in order to finance yet another round of hostilities with Spain. Finding a sympathetic ear in Queen Elizabeth, in 1589 she sends her fleet to Lisbon on his behalf with disastrous results. Now Dom António is not only smarting from three consecutive losses to the Spanish, his jewels – including the Mirror of Portugal – are now the property of Queen Elizabeth who decides to keep the stones to defray the costs of the ill-fated endeavor. A thrice defeated broke, and no doubt bitter Dom António decides to return to Paris to live out his days in exile. Meanwhile, Queen Elizabeth has the Mirror of Portugal set in a gold pendant and surrounded by enameled flowers which she hangs from a chain.

The diamond remains in English hands until the reign of Elizabeth’s successor James I, who allows his love-struck son Charles to take a group of stones from the royal collection and offer them to Spain in an attempt to win a betrothal to the Infanta, Maria Anna. Among this collection is the Mirror of Portugal, now re-set together with a large pearl. The attempt at this alliance with Spain – and marriage to the fetching Maria Anna prove unsuccessful. The rebuked Charles then decides – amidst the protests of Parliament – to marry Henrietta Maria of France, a Catholic.

Now crowned King Charles I, he finds himself – and his monarchy – in a constant state of poverty. When England becomes embroiled in a costly civil war, Charles sends his dutiful wife Henrietta to the Netherlands in an attempt to raise money for his throne. Unsuccessful in her venture to sell the Mirror of Portugal (plus another famous stone, the Sancy) along with other valuables from the Treasury to the Dutch, Henrietta finally is able to find a willing partner in the Duke of Épernon. She works out a deal using the diamonds to collateralize a loan from the Duke. When Charles I defaults on the loan, the Duke keeps the diamonds and recoups his losses by selling both stones to Cardinal Mazarin for his collection.

It is at this point the Mirror of Portugal becomes known as Mazarin III and the Sancy Mazarin I. While in the Mazarin collection, the diamond formerly known as the Mirror of Portugal’s weight decreases from its 1691 inventoried weight of 25 3/8 carats to 21 1/8 carats in the 1791 inventory.

Unfortunately, in 1792 during the upheaval of the French Revolution, the Mirror of Portugal, along with many other famous jewels, is stolen during the robbery of the Garde Meuble (National Treasury) and disappears forever.

Sources

• Balfour, Ian. Famous Diamonds, Woodbridge, Suffolk: Antique Collectors’ Club Ltd., 2009. Pp. 186-187
• Copeland, Lawrence L. Diamonds… Notable and Unique, United States: Gemological Institute of America, 1974. Pp. 76.
• McCarthy, James Remington. Fire in the Earth: The Story of the Diamond: New York: Harper Brothers, 1942. Pp. 100.
• Millar, Stephen. France’s Royal and Imperial Crown Jewels: 1792 – 2005. The Napoleon Series, © 1995-2005.