| The very finest, top quality ruby is so rare that it | | | | stones are often pinkish in hue and many are |
| has been the world's most valued gemstone for | | | | pastel in tone. Some, however, resemble the vivid |
| thousands of years. In fact, even today, flawless | | | | pinkish red hues from Burma. |
| top quality rubies are more valuable and rare than | | | | Rubies from Kenya and Tanzania surprised the |
| top quality colorless diamonds. A 16 carat ruby | | | | world when they were discovered in the sixties |
| sold at auction for US$227,301 per carat at | | | | because their color rivals the world's best. |
| Sotheby's in 1988. A 27.37 carat Burmese ruby | | | | Unfortunately, most of the ruby production from |
| ring sold for US$4 million at Sotheby's in Geneva | | | | these countries has many inclusions, tiny flaws |
| in May 1995, or $146,145 per carat. A 32 carat | | | | which diminish transparency. Rubies from the |
| ruby sold for US$144,000 per carat at Sotheby's | | | | African mines are rarely transparent enough to |
| in 1989. In contrast, eight D-color internally | | | | facet. However, their fantastic color is displayed |
| flawless diamonds over 50 carats were sold in the | | | | to full advantage when cut cabochon style. A few |
| past 9 years and the largest, a pear-shape of 102 | | | | rare clean stones have been seen which are top |
| carats, fetched a mere US$125,000 per carat. | | | | quality. |
| Top rubies are so rare even the world's top gem | | | | The most important factor in the value of a ruby |
| dealers must incessantly comb through wealthy | | | | is color. The top qualities are as red as you can |
| estate sales and auctions to find them. Clean | | | | imagine: a saturated pure spectral hue without any |
| bright stones in sizes above five carats are | | | | overtones of brown or blue. An intense pure, red |
| particularly rare. | | | | color, uniform color is the most valuable gem. |
| Ruby is the gem quality form of the mineral | | | | Clarity is also of secondary importance, but a fine |
| corundum, and one of the most durable minerals | | | | colored gem with slight flaws is still highly valued. |
| which exists, a crystalline form of aluminum oxide. | | | | Large sizes rubies are more rare than diamond |
| Corundum has a hardness of 9 on the Mohs scale | | | | and a value of fine gem ruby increases |
| and is also extremely tough. In its common form, | | | | significantly (more so than other gems) with |
| corundum is even used as an abrasive. Colors of | | | | increased weight. |
| Corundum other than red are known as Sapphire. | | | | The word red is derived from the Latin for ruby, |
| The element Chromium is responsible for the red | | | | ruber, which is derived from similar words in |
| color of this gem, but too much Chromium can | | | | Persian, Hebrew, and Sanskrit. The intensity of |
| actually turn corundum emerald green in color. | | | | color of a fine ruby is like a glowing coal, probably |
| Heat treatment is very common in ruby | | | | the most intensely colored substance our |
| gemstones (as is true for all forms of corundum) | | | | ancestors ever saw. It is no wonder they |
| and is used to dissolve "silk" inclusions, which | | | | ascribed magical powers to these fires that |
| results in a more transparent, more intensely | | | | burned perpetually and never extinguished |
| colored stone. The heat treatment is considered | | | | themselves. |
| permanent and does not usually detract from the | | | | After color, the other factors which influence the |
| value of the stone. | | | | value of a ruby are clarity, cut, and size. Rubies |
| The most famous source of fine rubies is Burma, | | | | that are perfectly transparent, with no tiny flaws, |
| which is now called Myanmar. The ruby mines of | | | | are more valuable than those with inclusions which |
| Myanmar are older than history: stone age and | | | | are visible to the eye. Cut can make a big |
| bronze age mining tools have been found in the | | | | difference in how attractive and lively a ruby |
| mining area of Mogok. Rubies from the legendary | | | | appears to the eye. A well-cut stone should |
| mines in Mogok often have a pure red color, | | | | reflect back light evenly across the surface |
| which is often described as "pigeon's-blood" | | | | without a dark or washed-out area in the center |
| although that term is more fanciful than an actual | | | | that can result from a stone that is too deep or |
| practical standard in the trade today. Myanmar | | | | shallow. The shape should also be symmetrical and |
| also produces intense pinkish red rubies which are | | | | there should not be any nicks or scratches in the |
| also vivid and extremely beautiful. Many of the | | | | polish. |
| rubies from Burma have a strong fluorescence | | | | Ruby sometimes displays a three-ray, six-point |
| when exposed to ultraviolet rays like those in | | | | star. These star rubies are cut in a smooth |
| sunlight, which layers on extra color. Burma rubies | | | | domed cabochon cut to display the effect. The |
| have a reputation of holding their vivid color under | | | | star is best visible when illuminated with a single |
| all lighting conditions. | | | | light source: it moves across the stone as the |
| Fine rubies are also found in Thailand. Thai rubies | | | | light moves. This effect, called asterism, is caused |
| tend to be darker red in tone: a real red, tending | | | | by light reflecting off tiny rutile needles, called |
| toward burgundy rather than pink, as Burma | | | | "silk," which are oriented along the crystal faces. |
| rubies do. This makes them very popular in the | | | | The value of star rubies and sapphires are |
| United States where consumers generally prefer | | | | influenced by two things: the intensity and |
| their rubies to be a darker red rather than a | | | | attractiveness of the body color and the strength |
| darker pink. Some Thai rubies have black | | | | and sharpness of the star. All six legs should be |
| reflections, a phenomenon called extinction, which | | | | straight and equally prominent. Star rubies rarely |
| can make their color look darker than it really is. | | | | have the combination of a fine translucent or |
| But Thai rubies can also have a rich vivid red that | | | | transparent color and a sharp prominent star. |
| rivals the Burmese in intensity. Sri Lankan rubies | | | | These gems are valuable and expensive. |
| can also be very beautiful. Many Sri Lankan | | | | |