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 600ï¿½C, 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.
The Dresden Green out of its setting.
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 ï¿½10,000.”
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 ï¿½30,000. 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 ï¿½20,000. 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 Brï¿½nn 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.
The Golden Fleece ornament with the Dresden White (top). The center third of the
ornament which encompasses the Dresden Green was saved from disassembly and remains
part of the present ornament. The top part of the ornament encompassing the Dresden
White was saved and is now part of the Dresden White’s ornament (see photo below).
The Dresden Green ornament on display in the Green Vault among other pieces of regalia.
The white diamond ornament to the left of it contains the Dresden White Diamond at its top.
The Dresden Green’s facet layout, captured from its Gemcad file. This design
originally appeared in the winter, 1990 issue of Gems & Gemology, and was
converted into Gemcad by Robert Strickland in 1998. It is the most faithful
retro-engineered replica of the Dresden Green I have ever seen, and thus, can
be checked off of the list of famous diamonds to be converted into Gemcad.
Another photo of the Dresden Green, photographed
from the underside with the culet facing outward.
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, and various sites scattered around the internet.