Information
INTRODUCTION RUBY
Ruby is the next hardest of the gemstones and the best examples can be more rare than Diamonds
Note that Ruby and Sapphire are actually both corundum, but of different colour Ruby- believed to be an antidote for poison, the gem was also attributed with prophetic powers, the stone apparently darkening to warn of impending danger.In Roman time Rubies from Greece engraved with dragons or dogs were especially prized. The gem is also extolled by Hindus as ensuring health, wealth and a joyous nature to the owner.
COLOR,CLARITY & CUT
Ruby and Sapphire are chemically very similar; both are corundum, only colour differentiates them due to chromium in ruby and titanium in Sapphire .For Ruby, the intensity of the red color is the primary factor in determining value. The ideal stone displays an intense, rich crimson without being too light or too dark. Stones which are too dark and garnety in appearance, or too light in color,are less highly valued. The finest Rubies display a color similar to that of a red traffic light. Rubies generally look best viewed with incandescent light or daylight (particularly around midday). Avoid fluorescent tubes, which have virtually no output in the red end of the spectrum, and so cause ruby to appear grayish.In terms of clarity, Ruby tends to be less clean than Sapphire. Buyers should look for stones which are eye-clean, i.e., with no inclusions visible to the unaided eye. In the case of some Rubies, extremely fine silk throughout the stone can actually enhance the value. Many Rubies also display a strong red fluorescence to daylight, and this adds measurably to the beauty of this gem..
Rubies often contain inclusions called ‘silk’, caused by needle-like crystals of rutile.
The inclusions sometimes form in such a way as to produce what is known as a ‘Star Ruby’. These are cut en cabochon orientated to display the star. They are highly prized and expensive. Of course, these can also be forged by engraving lines on the base of the cabochon and covering with a piece of reflective material or synthesized in the laboratory. Natural star stones rarely show the stars as bright and clear as the ‘forgeries’.
In the market, Rubies are found in a variety of shapes and cutting styles. Ovals are cushions are the most common, but rounds are also seen, as are other shapes, such as the heart or emerald cut. Slight premiums are paid for round stones, while slight discounts apply for pears and marquises. Stones that are overly deep or shallow should generally be avoided.Cabochon-cut Rubies are also common. This cut is used for star stones, or those not clean enough to facet. The best cabochons are reasonably transparent, with nice smooth domes and good symmetry. Avoid stones with too much excess weight below the girdle, unless they are priced accordingly.
ORIGIN:
The best Ruby comes from Burma(Myanmar) and the best colour is ‘Pigeon blood’, but stones of this quality are rare and very expensive. Thailand, Tanzania & Madagascar (formerly the Malagasy Republic)also produce stones but rarely of the quality of the Burmese stones. Sri Lanka ,which has greatest variety of gemstones ,also provides Rubies, most of which are pale, but occasionally intense reds are discovered. Pale red colours are actually classified as Pink Sapphire,New sources of stones are being discovered with regularity. Rubies are ‘the’investment stone. Large crystals over five carats are very rare and a lot is lost in cutting ,due to colour variations.
IMITATION:
Consequently ,synthetic ruby abounds ,with tons being produced every year Chatham from the USA also produces high-quality stones that are extremely difficult to detect without laboratory help.A particularly good synthetic ruby has been produced in Mexico under the name of ‘Ramaura Rubies’,created by the J.O. Crystal Company .A special fluorescent dopant is added to enable identification by the gemologist. The synthetic stones can be of such high quality that you may not mind whether you have a real Ruby or not –after all, if you don’t know whether the gem in your ring is real or synthetic, neither will your friends. The thing to avoid is paying the price of real for synthetic. If, however ,you decide that only the real thing will do ,then the only answer is to go to a reputable supplier .Inclusions and colour branding usually identify natural stones from synthetic, but of course this is the job of a qualified gemologist. Glass filling of fractures is becoming more common, so, if a stone is being bought as an investment ,then it is imperative to have it checked at a laboratory before purchase. The faking of natural rubies has been taken to a new level with synthetic ruby being purposely fractured by immersing a hot stone into a very cold water and then filling these fractures with glass. Therefore giving the impression that the stones are natural. The glass filling of rubies has now reached dangerous proportions, with very many in the market. They can easily deceive, being extremely difficult to identify for the layperson. Extreme care is therefore needed when purchasing -only buy from a reliable source.
Other red-coloured natural gems are sometimes confused with Ruby ,such as Spinels and red Garnets ,though both of these are singly refractive and not doubly refractive as is Ruby. Gem Ruby has been misidentified for hundreds of years.
VALUE
Prices are dependent on origin, color, size, and clarity: from a low of $100 to $30,000/ct. Visit our dubai online shopping and we can assist you with the right information about the value of Ruby and about any other gold stones.
RUBY GEMSTONE PROPERTIES
Composition | Al2O3 |
Hardness (Mohs) | 9 |
Specific Gravity | 4.00 |
Refractive Index | 1.762–1.770 (0.008) Uniaxial negative |
Crystal System | Hexagonal (trigonal) |
Colors | Various shades of red. Ruby is colored by the same Cr+3 ion that gives alexandrite and emerald their rich hues. |
Pleochroism | Strongly dichroic: purplish red/orangy red |
Phenomena | 6 or 12-rayed star |
Handling | No special care needed |
Enhancements | Frequently heated; frequently flux-healed; occasionally oiling, dying, surface diffusion |
Synthetic available? | Yes |
NAME,FAME & LEGEND
The name “Ruby” is believed to be derived from the Latin ruber, a word for red. According to Oriental beliefs, Ruby is the gem of the sun. It is also the birthstone of July.The 170-ct Black Prince’s ‘Ruby ’originally set in the helmet of King Henry V and worn at the battle of Agincourt is ,in fact, a Spinel; it is now set in the Imperial State Crown.