All About Sapphires
Sapphire colors
Blue is the most famous of the sapphire colors. The prized Kashmire and Burmese sapphires have a deep blue that is intense and velvety. These sapphires are not often seen on the market today. Sri Lankan (Ceylon) and Madagascar sapphires are the most common today, with a wide range of colors from light sky blue to dark blue. Other producers of blue sapphire are Australia, Tanzania, Thailand, Cambodia, and the USA (Montana).
Blue is the most famous of the sapphire colors. The prized Kashmire and Burmese sapphires have a deep blue that is intense and velvety. These sapphires are not often seen on the market today. Sri Lankan (Ceylon) and Madagascar sapphires are the most common today, with a wide range of colors from light sky blue to dark blue. Other producers of blue sapphire are Australia, Tanzania, Thailand, Cambodia, and the USA (Montana).
Colorless corundum is rare as faint shades of color are nearly always present. Many small white sapphires used in inexpensive jewelry as a diamond simulant are synthetic and white sapphire in general are relatively cheap.
Purple sapphire is rare, but found in Sri Lanka and Tanzania.
Iron and titanium impurities together may cause the purple hue of the
stone.
Much yellow sapphire is on the lighter side and usually free of inclusions. Heat treatment can produce a more intense yellow golden color. Beryllium-treated sapphire may be a brilliant yellow, pinkish orange, orange and recently vivid blue. These stones are found in Sri
Lanka, Thailand, Australia, Tanzania and Madagascar.
Padparadscha
is the Sinhalese word for a Sri Lankan lotus flower. This very rare
sapphire color should have a pink and orange color simultaneously.
Color, brilliance, size and clarity will determine the value of these
stones. Many stones of this color are beryllium treated and are priced much lower than a true padparadscha. A true padparadscha as well as the treated counterpart always have a hint of pink, they look the same so be careful and always buy from an accredited jeweller who will certify the sapphire.
Many sapphires that appear green consist of fine alternating bands of blue and yellow sapphire, which may be visible under the microscope. Green sapphires are found in Thailand, Sri Lanka, Australia, and Madagascar and are usually a dull green color.
Color
With blue sapphire, the most popular color, the intensity of blue as the most important factor. For example, you may have a huge stone of many carats, but if the color is a washed-out, weak blue, then the value of the stone will be lower. Look for a stone that has an intense, rich medium blue (royal blue) without being dark or inky (navy blue). Overall, sapphires that are too dark or too light in color are valued less. However, light blue sapphires often have a brilliance that is rarely found in the darker stones.
Lighting
Sapphires look best viewed with fluorescent light or daylight. Incandescent light is more red, and sapphires look less attractive in this lighting.
Sapphires look best viewed with fluorescent light or daylight. Incandescent light is more red, and sapphires look less attractive in this lighting.
Clarity
Sapphire tends to have less inclusions than ruby. Look for stones that are eye-clean. This means no inclusions that are visible to the naked eye. Actually, extremely fine silk throughout the stone can enhance the value of some sapphires. The famous sapphires from Kashmir have a velvety blue color which is caused by this fine silk. This silk is needed for the star effect in star sapphire, however, too much silk weakens the color, making it appear undesirably grayish.
Sapphire tends to have less inclusions than ruby. Look for stones that are eye-clean. This means no inclusions that are visible to the naked eye. Actually, extremely fine silk throughout the stone can enhance the value of some sapphires. The famous sapphires from Kashmir have a velvety blue color which is caused by this fine silk. This silk is needed for the star effect in star sapphire, however, too much silk weakens the color, making it appear undesirably grayish.
Cut
Various shapes and cutting styles are common with sapphires. Ovals, cushions, and rounds are seen, as are other shapes, such as the heart or emerald cut. Round stones can command a small premium. Sapphire crystals are hexagonal in habit so when they are cut in a round shape a lot of the rough is lost so this is why round shapes are more expensive. Oval cut sapphires use most of the rough and are more common. Cabochon-cut sapphires are also common. Used for star stones, the best cabochons are somewhat transparent, with smooth domes of good symmetry.
Various shapes and cutting styles are common with sapphires. Ovals, cushions, and rounds are seen, as are other shapes, such as the heart or emerald cut. Round stones can command a small premium. Sapphire crystals are hexagonal in habit so when they are cut in a round shape a lot of the rough is lost so this is why round shapes are more expensive. Oval cut sapphires use most of the rough and are more common. Cabochon-cut sapphires are also common. Used for star stones, the best cabochons are somewhat transparent, with smooth domes of good symmetry.
Common Sapphire treatments
The most common treatment for sapphire is heat treatment. Stones are heated (generally before they are cut) to between 1700 to 1800 degrees Celsius (3100-3300 degrees F) for several hours. Almost all sapphires today are heated, and the stones of rich blue that are not heated can command enormous prices in today's market. Some blue sapphires may also be diffusion treated and care must be taken not to polish these stones as the color is only skin deep and comes off when the stones are polished, though this treatment is more common for star sapphires. Rich blue sapphires are now on the market that are diffusion and beryllium treated. Beryllium treatment is being used to produce stunning orange and red colors that were once rarely seen. All sapphire treatments should be fully disclosed by any reputable dealer.
The most common treatment for sapphire is heat treatment. Stones are heated (generally before they are cut) to between 1700 to 1800 degrees Celsius (3100-3300 degrees F) for several hours. Almost all sapphires today are heated, and the stones of rich blue that are not heated can command enormous prices in today's market. Some blue sapphires may also be diffusion treated and care must be taken not to polish these stones as the color is only skin deep and comes off when the stones are polished, though this treatment is more common for star sapphires. Rich blue sapphires are now on the market that are diffusion and beryllium treated. Beryllium treatment is being used to produce stunning orange and red colors that were once rarely seen. All sapphire treatments should be fully disclosed by any reputable dealer.
All the rest you need to know
Sapphires come from Thailand, Sri Lanka, Madagascar, Tanzania and Australia. The United States, Cambodia, Nigeria, Kenya and China also produce some sapphires. Perhaps the most famous sources for sapphires are the Kashmir region of India, and Burma. Discovered over 100 years ago, the Kashmir sapphire has a lovely, velvety blue color prized by gem lovers. Burmese sapphires can also be fine, but like the Kashmir region, these two areas today produce very little material.
Sapphires come from Thailand, Sri Lanka, Madagascar, Tanzania and Australia. The United States, Cambodia, Nigeria, Kenya and China also produce some sapphires. Perhaps the most famous sources for sapphires are the Kashmir region of India, and Burma. Discovered over 100 years ago, the Kashmir sapphire has a lovely, velvety blue color prized by gem lovers. Burmese sapphires can also be fine, but like the Kashmir region, these two areas today produce very little material.
Today Sri Lanka and Madagascar produces most of the fine
sapphires on the market. You can find a wide range of beautiful blues,
from soft sky blue colors to deeply saturated hues. In addition, the
Kanchanaburi region in Thailand and the Pailin region in Cambodia are
renowned for deep blue sapphires. Tanzania, an old producer of sapphires
in other colors, is now starting to produce blue sapphire from new
deposits in the south.
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