|In November, Sotheby’s in Geneva sold a large, drop-shaped natural pearl pendant for more than $36m. The pearl once belonged to French Queen Marie Antoinette.|
In May, the 6.16-carat rare blue diamond known as the Farnese Blue brought $6.7m.
Saturday, 29 December 2018
Friday, 28 December 2018
|A combination of black and white, gray is a non-spectral color. In their purest forms, gray color diamonds come quite close to colorless stones.|
Among colored diamonds, gray diamonds are relatively unknown due to their extreme rarity. Far more rare than yellow and brown diamonds, gray diamonds are in the lower range of fancy colored diamonds prices ... it is so attractive that they can be considered an alternative to white colorless diamonds.
|Most gray colored diamonds get their color due to a high concentration of hydrogen, and rarely boron like blue diamonds.|
|In the niche of gray diamonds, there are nearly endless options. The human eye can distinguish up to 500 shades of gray and this is probably the number of gray diamond colors there are. |
Gray diamonds are graded in the following intensity levels: Light Gray, Fancy Light Gray, Fancy Gray, Fancy Dark Gray, and Fancy Deep Gray.
|There are few notable gray diamonds because they barely exist. Two of the most famous diamonds in the world are blue diamonds with a gray modifier: the Hope Diamond and the Wittelsbach Diamond.|
The most famous gray colored diamond is the Sultan of Morocco. The diamond has a cushion cut, a blue hue and weighs 35.27 carats.
Thursday, 27 December 2018
Wednesday, 26 December 2018
|Spinel is the magnesium aluminium member of the spinel group. It has the formula MgAl2O4. Balas ruby is an old name for a red variety.|
After the 18th century the word ruby was only used for the red gem variety of corundum and the word spinel became used. "Balas" is derived from Balascia, the ancient name for Badakhshan. The Badakshan Province was for centuries the main source for red and pink spinels.
|Spinel is most famous for its deep red variety that closely resembles ruby. The two gemstones can be very difficult to distinguish. Until the late 19th century, there was no distinction made between ruby and red spinel, as they look identical and are found in the same localities. Many famous old "rubies" were discovered to be spinel.|
Mining in Afghanistan has a history over 2,000 years as gold, silver and precious stones were routinely mined. Afghanistan's ruby/spinel mines were mentioned in the writings of many early travellers.
|The Badakhshan mines were of great importance during the period from 1000–1900 AD. They were the source of many of the finest early red spinels in gem collections around the world, such as those in the crown jewels of Iran, the collection in Istanbul's Topkapi, Russia's Kremlin and Diamond Fund, and England's Tower of London.|
Imperial State Crown
|During the Soviet occupation, mining of all Afghan gem and mineral deposits was controlled by the state. However, since many mines lay in inaccessible areas, such mining became an important source of income for the rebels. |
|In the late 1980s, large reddish spinels were reported from the Pamir mountains of what is now Tajikistan. One 532 carat rough yielded cut gems of 146.43 and 27.81 carats. Ruby was also reported in eastern Tajikistan, near the border with China, in the early 1980s. |
Political difficulties and rugged terrain make Afghanistan a difficult country to explore, and Tajikistan is no better.
|The Hope Diamond had a counterpart in the collection it was in — the Hope Spinel.|
Both belonged at one time to powerful London banker Henry Philip Hope, who died in 1839. The 45.52-carat Hope Diamond now resides in the National Museum of Natural History at the Smithsonian, while the 50.13-carat spinel headlined Bonhams’ Fine Jewelry sale in London on September 24, 2015. It was expected to fetch between £150,000 and £200,000. It made £962,500
Tuesday, 25 December 2018
|Described by gem aficionados as “emerald by day, ruby by night,” alexandrite is a very rare color-change variety of the mineral chrysoberyl. |
Alexandrite deposits were first discovered in 1830 in Russia’s Ural Mountains. Those first alexandrites were of very fine quality and displayed vivid hues and dramatic color change.
|The spectacular Ural Mountain deposits didn’t last, and today most alexandrite comes from Sri Lanka, East Africa, and Brazil. The newer deposits contain some fine-quality stones, but many display less-precise color change and muddier hues than the nineteenth-century Russian alexandrites.|
Fine alexandrite is green to bluish green in daylight and red to purplish red in incandescent light. Alexandrite is most often available in mixed cuts. Its extreme rarity means it is often cut to save weight.
|Good quality alexandrite has few inclusions. Rarely, needle-like inclusions create a cat’s-eye. Most cut gems weigh less than one carat. Larger, high quality gems rise in price dramatically.|
Production from Russian mines is very limited today. Sri Lankan alexandrites are generally larger but their colors tend to be less desirable. Alexandrites from Brazil have been found in colors that rival the Russian material, but production has decreased significantly.
Monday, 24 December 2018
|Victoire de Castellane is a French jewellery designer of Christian Dior's fine jewellery division. She started her career alongside Karl Lagerfeld at Chanel, overseeing the house’s costume jewelry designs for 14 years.|
Her sources of inspiration include a global mix of pop culture. Each year de Castellane creates a High Jewelry collection and at least one Fine Jewelry collection for Dior Joaillerie, as well as numerous one-off, bespoke pieces for individual clients.