-Mined in Thailand , Burma , Sri Lanka and Africa .

Rubies are the red varieties of the corundum family of gems and only in the U.S is there a color-minimum for this classification. The blue variety of this family is the sapphire, and so it is easy to understand that rubies will often have bluish undertones to them, while sapphires often have reddish undertones. Rubies are rated 9 on the Moh scale and they are extremely durable over time. As rubies come in a wide selection spanning the palest pink to the blackest blood reds, the U.S has instated a certain descriptive limitation on what's termed a ‘ruby' and what's termed a ‘pink sapphire'. Technically, any corundum gem that is too pink will not be called a ‘ruby' in the U.S, although in Europe and the rest of the world, this distinction will not be made. Generally, rubies are evaluated for strong, red fluorescence and high-quality gems should have very few brown, gray or black color influences. There are also many gems misrepresented as rubies and this is something to watch out for. Garnets, for example, are substituted for rubies on a regular basis, and are called “ Arizona rubies” at times to confuse the customer. Some other misleading names are: “Silberian ruby” (actually red tourmaline), “Spinel ruby” (spinel), “ Chatham ruby” (a synthetic imitation), “Ramura ruby” (synthetic), “Almandine ruby” (red garnet), “ Cape ruby” (garnet), “Balas ruby” (red or treated spinel), “Bohemian ruby” (red garnet) and “Australian ruby” (red garnet). The ruby's color is very much depended on the type of light used to view it; viewed in warm light or against a yellow piece of paper, a ruby will look its very best shade of red. Therefore always view a ruby against a white backdrop and in several types of light to compare between the different results.

Remember- treated rubies should always cost less than natural, untreated ones. Diffusion treatment and heat-treatment are the most common technique used to improve rubies and often they are also oiled to improve color. They new lab-grown synthetics can easily pass for authentic stones, even after an examination from a certified appraiser-gemologist. An un-heated ruby of good (or better) quality can cost as much as 50% more than a treated ruby of the same grading. Moderate heat will not affect price adversely, but high heat will lower value by 5% in good grade gems and by as far as 15% in extra fine gems. If the ruby is also applied with a glass residue to enhance its brilliance or deepen color, it will loose even more value-; depending on the grade of gem, it will loose 5% in ‘good' grade gems, 15% in ‘fine' graded gems and even 20% in very fine gems. If it has been fracture-filled, you can reduce it automatically by atleast 10% and then reduce steadily from there, depending on how well it's graded. But the point to remember about fracture-fillings is that they reduce worth substantially- up to 50% in all quality grades.

In general, good quality rubies with very few inclusions are sold for about $3000-$4000 per carat for 1-carat-stones. Anything heavier than that will cost far more per carat weight.

Rubies come in deep, totally opaque colors but they also come in translucent, see-through reds, so don't be alarmed in you are presented with several shades that don't seem to fit in the misconception usually associated wit this gem-type. Poor grade, very opaque rubies can sell for as little as $20 per carat and deep red, clear stones that are 3 or more in carat weight can sell for $150,000-$200,000 per carat. The usual price range is $700-$6000 for anything between half a carat and 1-carat rubies. For 1 to 2 carats the price is around $1000-$13,000 (depending on quality) and for 2 to 4 carats the price is $1500- $20,000 per carat. They are mostly cut in faceted styles with cabochon cuts costing slightly less than faceted gems. The” star ruby” in the one variety commonly cut as a cabochon, and it displays the six-ray star effect. This effect can now be simulated in synthetic lab-grown labs, so

The most prized, fine grade rubies come from Thailand ; a country that produces the widest ranging rubies in the market. Quite like the Ceylon rubies, Thai gems are encountered frequently, but for the most part they are pale in color and worth very little. The greatest percentage of these isn't worth very much, as they don't hold any solid color, and they are of relatively poor quality. However, a very tiny percentage of Thai stones are considered the finest in the world, holding deep bluish undertones that support the basic red hue and make the ruby deep and beautiful. Very fine Thai rubies are so

Burmese rubies from the Mogok area are extremely expensive because they seem to epitomize the sheer redness that a ruby is supposed to be imbued with. However, they vary greatly in tonality, coming in a wide array of darker and lighter tones and with different undertones of color to them that can drive the red to violet or blue. As stated in the beginning of the text, the basic purity of the color is the determining factor in deciding worth, and the very dark reds or very pale reds sell for less than the more solidly-red stones. Burmese rubies are held in high regard because they consistently hold that redness in all lights- the solid, medium hues can be held to all types of light, and will sparkle with a pure red halo, with very few sullying undertones to them. Some types of African and Asian rubies also have this quality; ‘holding' their hues in different light settings. The last few years have seen the introduction of rubies from Pakistan , China , Vietnam , Cambodia and Kenya . African rubies are usually much browner in tone, or sometimes even yellowish and orange., and these are mostly a cheaper grade of ruby that sell for less than either Thai or Burmese.

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