Link to a large photo:
Dresden Green Diamond (in its hat clasp ornament)
In the rough, greenish diamonds tend to occur as one of three types: a stone, often a crystal shape, possessing a light tinge rather like the color of water in a swimming pool; a stone with a dark green skin; a yellowish-green stone characterized by a degree if lubricity. After being cut and polished, diamonds of the first and second types usually lose their greenish color to become white gems or, alternatively, light yellow stones known as "silvery capes". The few truly green faceted diamonds therefore originate from the third type. The famous collection of De Beers Fancy Colored Diamonds, which has been displayed throughtout the world includes some beautiful examples of green diamonds.
Since this is the story of a truly rare gem, a scientific explanation for the phenomenom of green diamonds is needed. The green color is usually caused by the crystal's coming into contact with a radioactive source at some point during its lifetime, and in geological terms, this is measured in millions of years. The most common form of irradiation diamonds chance into is through bombardment by alpha particles which are present in uranium compounds or percolating groundwater. Long exposure to these particles forms a green spot on the surface of the diamond, or sometimes produces a thin green coating which is only skin deep and can easily be removed during the faceting process. But bombardment by beta and gamma rays well as neutrons will color the stone to a greater depth and in some cases turn the whole stone's interior green.
Heating the stone might sometimes improve the color but care must be taken to keep the temperature below 600°C, because at this temperature the green color is likely to turn to a light yellow or brown. The change in color is caused by the change in the crystal's lattice structure. Before bombardment by radioactive particles the crystal's lattice was stable but the initial radioactive shock was sufficient to disturb the equilibrium and produce a green coloration. Tempering will distort the lattice further abd produce another change of color. This phenomena is analogous to a piece of elastic that has been overstretched; it will stretch back so far, but never returns to its original length. Similarly, after a treatment the diamond's lattice remains permanently distorted.
Research has disclosed that green or irradiated diamonds are more common from alluvial deposits, although they are found in primary sources, usually in the upper part of the diamond-bearing volanic pipe, but green diamonds of any size are rare. The Dresden Green, which probably weighed over 100 (old) carats in its rough form, is unique amoung world famous diamonds. It was originally probably an elongated unbroken stone since greenish diamonds rarely occur as cleavages.
The Dresden Green gets its name from the capitol of Saxony where it has been on display for more than 200 years. The earliest known reference to its existence occurs in The Post Boy, a London new-sheet of the 1700's. The issue dated October 25th - 27th, 1722 included this article:
"On Tuesday last, in the afternoon, one Mr. Marcus Moses, lately arrived from India, had the honor to wait on his Majesty [King George I (ruled 1714-27)] with his large diamond, which is of a fine emerald green colour, and was with his Majesty near an hour. His Majesty was very much pleased with the sight thereof. It is said there never was seen the like in Europe before, being free from any defect in the world; and he has shown his Majesty several other fine large diamonds, the like of which 'tis said were never brought from India before. He was also, the 25th, to wait on their Royal Highnesses with his large diamond; and they were surprised to see one of such largeness, and of such a fine emerald color without the help of a foil under it. We hear the gentlemen values it at £10,000."
Marcus Moses was an important diamond merchant in London during the first part of the 18th century - he had once been involved with the Regent Diamond.
Another early reference to the Dresden Green is found in a letter dated from 1726, from Baron Gautier, the "assessor" at the Geheimes Rath's Collegium in Dresden, to the Polish ambassador in London, which speaks of the green diamond being being offered to Frederick Augustus I (1694-1753) by a London merchant for £30,000. This ruler, known as Augustus the Strong, was responsible for the construction of some great buildings in Dresden, which he duly filled with great collections of rare and expensive treasures - sculptures, paintings, and objets d'art. He accumulated a collection of crown jewelsas the ruler of Saxony, and when he was elected to the throne of Poland in 1697 he commanded new regalia be made for his coronation. Frederick Augustus set aside a group of rooms in Dresden Castle to house his collection of jewels and other treasures, and named them the Green Vault, their interior decoration being trusted to Persian designers. The final result was considered to be one of the finest examples of Baroque. Nowadays, the contents of the Green Vault is housed in a contemporary Albertinium Museum, built on the site of the original castle that was destroyed during World War II.
A model of the green diamond was owned by the eminent physicist Sir Hans Sloane (1660-1753), whose collection of books, manuscripts and curiosities formed the basis of the British Museum. When Sloane retired from active work in 1741 his library and cabinet of curiosities had grown to be of unique value and on his death he bequeathed his collection to the nation, on the condition that Parliament pay his executors £20,000. The bequest was accepted and went to help form the British Museum, opened to the public in 1759.
Neither George I nor Frederick Augustus I purchased the green diamond; instead it was the latter's son, Frederick Augustus II (1733-1763) who became its first royal owner. He bought the Dresden Green from a Dutch merchant named Delles, at the Leipzig Fair in 1741. Various figures are given for the purchase price but the most interesting was found in a letter to Frederick the Great, King of Prussia (1712-1786), which states that "For the seige of Brünn the King of Poland was asked for heavy artillery. He refused due to the scarcity of money; he had just spent 400,000 thaler for a large green diamond." On orders of Frederick Augustus II, the court jeweller, Dinglinger, set the diamond in the Decoration of the Golden Fleece, but this setting lasted for only four years and was broken up in 1746. The king then commissioned the goldsmith Pallard in Vienna, to design another Golden Fleece incorporating both the Dresden Green and the Dresden White, a cushion-shaped diamond weighing 49.71 carats.
From 1756 to 1763 during the continued hostilities of the Seven Years War, the contents of the Green Vault were removed for safety to the fortress of Königstein, located in southeast Dresden by the Elba River. Several years after the war, which saw the defeat of Saxony, Pallard's Golden Fleece ornament was also broken up. In 1768 another jeweller, Diessbach, worked the green diamond into a hat clasp along with two other white brilliants, weighing almost 40 carats total, and a number of smaller diamonds. The Dresden Green survives in Diessbach's ornament today.
In 1806 Saxony became a kingdom and the royal line continued until 1918 when the last king abdicated. The contents of the Green Vault remained on display to the public until the beginning of World War II. In 1942 they were removed again to Königstein, thus escaping the shattering air raid by the Allied Forces on the night of February 13th, 1945 which devasted Dresden. Later that same year the Soviet Trophies Commission, which had made its headquarters in Pillnitz Castle near the center of the ruined city, took the contents of the Green Vault to Moscow, the Crown jewels being among the first items to travel there. They were returned in 1958.
The Gemmological Institute of America examined the stone in 1988. The Dresden Green Diamond was proved to be not only of extraordinary quality, but also a rare type IIa diamond. The clarity grade determined by GIA was VS1 and the gem has the potential of being internally flawless. (This means that the stone's flaws are near the outer surface, probably the pavilion of the stone, where a slight re-cutting could remove them and improve the clarity of the stone.) The gem measures 29.75 × 19.88 × 10.29mm. Unbelievably, the GIA graded the symmetry good and the polish very good. This is amazing for a diamond cut prior to 1741. Also, the Dresden Green has a natural green body color. This is extremely rare. Diamonds with green skins or scattered green patches are more common.
In the summer of 2000, Ronald Winston completed arrangements for the Dresden Green to be exhibited in October, 2000, in the Harry Winston Gallery at the Smithsonian Institution, alongside the world's most famous diamond – the Hope. The 40.70-carat Dresden Green – the largest and finest natural green diamond ever found, has long been considered a "sister" to the Hope Diamond, which it closely matches in size, intensity of color, and historical importance. Friday, October 14th, marked the official public opening of this remarkable exhibition.
It was the twelve-year quest of Ronald Winston to bring these two diamonds together. "There is only one other diamond, the Dresden Green, which comes close to the Hope Diamond in rarity and uniqueness," said Ronald Winston. "I always hoped that in my lifetime I would be able to witness the Hope Diamond and the Dresden Green on exhibit together. This would have been the crown in my father's 'Court of Jewels,' an unparalleled collection which toured the country in the 1950's and included some of the most famous diamonds in history."
The Dresden Green remained at the Smithsonian until January of 2001, when it returned the Albertinium Museum in Dresden, where it remains to this day. Sources: The Harry Winston website, Famous Diamonds by Ian Balfour, The Nature of Diamonds by George E. Harlow, the Gemstone Forecaster.