DIAMOND SCIENCE & MYTH

For all the beauty and complexity of a well-cut diamond, they are the simplest of gemstones in the chemical sense: pure carbon, the same as the graphite in a pencil. They are formed under intense heat and pressure deep within the earth, and are forced to the surface by geological events.

Diamonds are harder than any other material on earth, earning them a 10 on the Mohs' scale of hardness. They can only be cut by other diamonds. Their hardness and other special qualities, such as how they refract light, allow them to be cut into the amazing gems we know today.

Gem-quality diamonds are mined around the world, but the largest producers are South Africa and its neighbors. Russia, Australia and Brazil are also major producers. Diamonds come from the mines in crystals, often with eight sides. As much as 60 percent of the original crystal is cut away to create a round brilliant diamond.

Diamonds have been at the heart of myth and legend since their discovery. Medieval knights wore them uncut on their armor in the belief that they could make a person invincible, a myth no doubt related to the stone's hardness. There are legends of a diamond that could reveal the guilt or innocence of a person. Diamonds could also drive away the devil, and in the days when gems were believed to cure disease and ill fortune, diamonds were thought to amplify the magical powers of other stones a person wore.

Almost universally, diamonds have been associated with virtue, purity, strength, wealth, power, and love - and, not surprisingly, diamonds have been associated with sex, too. So it was a small jump for diamonds to become the modern symbol of love - diamond wedding rings have been popular for hundreds of years. They were believed to ensure fidelity and strengthen emotional bonds. Today, they are the preferred gift for all manner of romantic occasions.

There is one important footnote to the magic of diamonds: the magic was lost if the stone was acquired by purchase. When found or given as a gift, however, it would convey its power to the recipient, which no doubt accounts for how diamonds became such a popular gift between lovers.

1 CT. Certified Oval Diamond Solitaire Ring in Platinum (G-H/VS2)
ITEM #: 17783937
$6899.00

DIAMOND CARE

While diamonds are the hardest minerals, they still require some care to keep them looking their best and to protect them from loss or damage.

A regular professional cleaning is recommended. Diamond jewelry can easily acquire a buildup of dirt, makeup and other materials that diminish its brightness, especially if it's worn every day. Many jewelers, including Zales, offer professional cleaning. Avoid using ultrasonic cleaners if your diamond has a serious crack or inclusion. The vibrations of these cleaners can enlarge such flaws.

What could possibly scratch a diamond? Another diamond. To prevent such scratches, separate diamond jewelry in your jewelry box. Diamonds also can scratch other gems or jewelry, especially soft items like pearls. And even though diamonds are hard, they can be brittle, especially along thin edges. Try not to wear your diamond when it might be struck sharply, and if you have an especially thin cut, keep it protected.

Perhaps even more distressing than chipping a diamond is losing one. When you go in for cleaning, ask the jeweler to check the setting and make sure the stone is secure. If it seems loose, bring it in for repair immediately. Also avoid setting diamonds in very soft metals like 24k gold, which bends easily.

3 CT. Certified Heart-Cut Diamond Solitaire Ring in Platinum (H-I/SI2)
ITEM #: 17786302
$31399.00

DIAMOND CARAT WEIGHT

Carat is the term used to describe the weight of any gemstone, including diamonds. Although the definition of a carat has changed over time, since 1913 the international standard has been 200 milligrams, or 1/5 of a gram. Often, jewelers describe carats in 1/4 increments.

In jewelry pieces with more than one diamond, the carats may be described in terms of total carat weight (TW). This is the combined total weight of all the stones in the piece.

Diamonds can range in size from a fraction of a carat to several carats. Given the rarity of large stones, however, the price increases rapidly with size; therefore, a single 2-carat diamond will cost much more than two 1-carat diamonds. Very large diamonds with good color and clarity are very rare.

Expect to pay a premium for stones that are above a full carat weight. For example, a .95 carat diamond will cost a bit more than a .90 carat stone, but a 1-carat stone will cost significantly more than a .95 carat stone.

Because round brilliant cuts follow exact standards, you can make a good estimate of the carat weight of the stone based on the stone's diameter. The following chart compares the relative sizes of stones and describes how much a round brilliant diamond of a certain size is likely to weigh. This method doesn't work as well for other cuts or shapes, though, since some are thicker or thinner than others; nor does this chart apply to colored gemstones, which have a different density from diamonds.

DIAMOND CUTS AND SHAPES

In the strictest definition of the term, "cut" is not the same thing as "shape" - for example, the most popular cut for a diamond is the round brilliant cut, but there are also round Swiss cuts, round Old European cuts, and round 144-facet cuts. For the most part, however, the terms are used interchangeably, including on this site.

The 58-facet round brilliant cut is the most popular because of its fire and brilliance. (These terms describe the intensity of the color and brightness of the light one sees in a diamond.) This is achieved by cutting the stone to very exacting mathematically-determined proportions so as much light as possible is reflected out the top of the diamond.

The cut of a diamond refers not only to the shape of the diamond and number of facets, but also to the quality of the cut. A diamond with uneven or poorly proportioned facets won't be given the same grade of cut as an ideally proportioned and masterfully cut stone. This information will be found on the certificate of a certified diamond.

Although most diamonds on the market today are round brilliants, there are many different shapes available. The following chart shows some of the most popular shapes:

1 CT. Certified Radiant-Cut Diamond Solitaire Ring in Platinum (G-H/VS2)
ITEM #: 17783648
$24499.00

DIAMOND CLARITY

It is very common for diamonds to be formed with slight imperfections. These are known as "inclusions" and can come in many forms, including tiny white points, dark dots, or feathery cracks. The fewer inclusions, the more the stone is worth. A diamond's clarity ranking is determined by the number, size, type and placement of the inclusions.

A stone with only a few hard-to-see pinpricks located near the edge, where they can be covered by the mounting, has better clarity than a stone with a crack located right under the table (the large top facet of the stone). Cracks from the surface to the interior are especially dangerous because the diamond could break if hit the wrong way. On the other hand, small nicks and chips on the surface are often of little concern because they can be polished away.

For the most part, diamonds used in jewelry are clean to the naked eye. In a certified diamond, the cracks are charted on the certificate and act as a fingerprint for identifying a particular stone.

The following is the GIA clarity scale, along with corresponding definitions for different clarity grades, which is very commonly used in the United States:

FL
FLAWLESS
Free from all inclusions orblemishes at 10x magnification.

IF
INTERNALLY FLAWLESS
No inclusions visible at 10x,insignificant surface blemishes.

VVS1VVS2VS1VS2
MINOR INCLUSIONS
Difficult to see face-up at 10x.

SI1SI2
NOTICEABLE INCLUSIONS
Easy to see at 10x.

I1I2I3
OBVIOUS INCLUSIONS
Easily visible to unaided eye.

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DIAMOND COLOR

Most diamonds appear colorless but actually have slight tones of yellow or brown. The closer the stone comes to colorless, the more valuable it is. Diamonds are graded on a color scale ranging from D (colorless) to Z (heavily tinted.) Only a highly skilled professional will detect any color in E or F stones, and the color in diamonds rated up to J will be virtually invisible when set in a ring or other jewelry.

Color is only one of the four C's so even when a stone has a visible tint, such as K or above, it can still be very lovely if it has good clarity and cut. How the diamond is set can make a difference, too; you might not want to put a truly colorless diamond in a yellow gold setting since the yellow color will reflect in the stone. On the other hand, a slightly yellow stone will appear whiter in a yellow gold setting.

Diamonds also come in a wide variety of other colors, including red, blue, green and a bright yellow known as "canary." These are graded as Z+ and are known as "fancy" diamonds. Ones with good color are very rare and can sell for much more per carat than white diamonds.
The following is the GIA color scale, which is very commonly used in the United States:

DIAMOND

Every diamond is different, incorporating a complex constellation of factors that determine the rarity of each stone. Although gemologists train for years to master the art and science of diamond appraisal, with a little basic instruction, anyone can learn how to read an appraisal and compare the grades of different stones.

Each diamond is as unique as the person who owns it. Just as a diamond reflects the color of the light it bears, it should also reflect the personality of the individual who wears it. Here lies the art of selecting a diamond, for yourself or as a gift.

Your knowledge of yourself, if you are buying for yourself, or your knowledge of a loved one, if the diamond is a gift, is expressed in your selection. Through your choice of a diamond, you are making a public statement about the loved one--and about your relationship--and that statement is repeated every time the diamond is worn.

This is why, for many women, there is such mystique in diamond jewelry gifts, and why, for many men, there is such uncertainty in its selection. What is important in the selection of a diamond has little to do with the cost of the jewelry and much to do with the richness of the relationship.

Truly flawless diamonds are very rare, and very expensive, so you will seldom face the task of selecting a perfect diamond. It is a fairly simple matter to find beautiful diamonds with no flaws visible to the naked eye and buy them at reasonable prices.

Diamonds are graded using a system that judges the stone on its color, clarity, cut and carat weight - commonly known as the "four C's." Diamonds of uncommonly high quality and size are often sold as "certified diamonds" and come with a certificate that proves the stone's value. Even non-certified diamonds, however, should be evaluated using the four C's to help determine cost.

In this section, you will learn what each of the C's means and how it affects the value of the diamond. Although it takes a trained eye to actually see the qualities described here, knowing what they mean can help you make a good choice in selecting your diamond.

1 CT. T.W. Diamond Frame Buckle Ring in 10K White Gold
ITEM #: 17693417
$999.00

2 CT. T.W. Champagne and White Diamond Earrings in 14K White Gold
ITEM #: 17727801
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TOPAZ

Topaz, and especially blue topaz, has grown in popularity over the years. The "pure" topaz color is yellow, and was often confused with chrysolite, the yellow variety of peridot. However, the use of distinct colors has helped topaz come into its own. Blue topaz in particular is popular in jewelry today. It has a watery blue similar to aquamarine, but often without the green overtones, and its hardness and good clarity make it an excellent gem. The blue color is often enhanced through heat-treatment and irradiation.

Topaz was believed to have incredible medicinal powers in the Middle Ages, even against the plague. For a healthy individual, it brought about a pleasant disposition and patience and was a symbol of fidelity and love.

Blue topaz is December's birthstone.

Pale blue to pink to yellow

A mixture of silicon, aluminum, fluorine and hydroxyl. Comes in many colors, with blue most common. Mohs' hardness rating of 8.

Large Oval White Topaz Ring with Diamond Accents in 14K White Gold - Size 7

$379.00

RUBY

Along with the emerald and sapphire, ruby is one of the most prized colored gem available. The main quality of the ruby is its bright red color. The best color usually comes from Burma and is very costly; stones from Thailand are darker but clearer and much more common. Only red stones are called rubies. If the color is too light to be called red, it is a pink sapphire.

Corundum, the main material of ruby, is the second-hardest material known after diamond. Inclusions and flaws are fairly common, and many rubies are treated to enhance their color. In general, one should look for a bright red stone with as few inclusions as possible. Synthetic rubies offer good color, clarity and size, and are more affordable.

Rubies were the most valuable gems in ancient Southeast Asia, where they are found. A fine ruby had all sorts of magical powers. Its color was thought to come from an undying flame inside the stone - or, in some legends, a piece of the planet Mars - and it allowed its owner to live in safety, even in the midst of enemies. It was believed to bring its owner all kinds of protection and to stop bleeding. In Burma, it could make one invincible - as long as it was embedded in the skin. In more modern times, rubies became the symbol of love and passion.

Ruby is July's birthstone.

Various shades of red

Corundum (aluminum oxide), the same family as sapphire, with the color coming from chromium. Mohs' hardness rating of 9. Lab-Created Ruby Cathedral Ring in 10K Gold with Diamond Accents

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Oval Ruby Fashion Ring in 14K Gold with Diamond Accents

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TOURMALINE

The name tourmaline derives from the Singhalese word "turamali" meaning gemstone. Known as the "Rainbow Gemstone", tourmaline comes in every color of the rainbow and most tourmaline gemstones are multi-colored. Gem cutters focus on bringing out the deepest color when cutting tourmaline. Still, when viewed from different angles a tourmaline may exhibit several different colors.

Tourmaline is reputed to have a powerful positive influence on love and friendship. With a Mohs' hardness rating of 7 to 7.5, tourmaline is a very durable and easy to maintain gemstone perfect for everyday wear.

Any color to multi-colored to opaque black

Primarily composed of sodium and boro-silicate hydroxide. Mohs' hardness rating of 7 to 7.5.

MOTHER OF PEARL

Mother of pearl is the iridescent internal layer of mollusk shells and is composed of the same material as pearls. Though technically not a gemstone, mother of pearl is used in all types of jewelry from mother of pearl watch faces to mother of pearl fashion jewelry.

Iridescent


Composed of nacre, the same substance as pearls








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$99.00

EMERALD

Emerald is one of the most valuable gems on the market. The brilliant green of a fine emerald is unmatched by any other stone, and the extreme rarity of top-quality emeralds - the most prized emeralds come from just a handful of mines in Columbia - make it fairly costly. However, there are supplies of emeralds coming out of other mines.

Almost all emeralds have inclusions in them; the fewer these impurities, the rarer and costlier the stone. Because of these inclusions, emeralds can be brittle, so protect your emeralds from hard contact when you wear them. Ultrasonic cleaners, which use vibrations to remove dirt and buildup, can be dangerous to heavily included emeralds. Natural emeralds also tend to have thin scratches on the surface. A layer of wax or oil is usually applied to smooth out their appearance and enhance their color. This layer may have to be replaced professionally every few years.

It was believed to sharpen wits, bring wealth, foretell the future, tell whether a lover was lying and cure all types of evil and illness.

Emerald is the birthstone of May.

Green to bluish green.

The most valuable form of beryl and one of the world's most precious gems. Color comes from chromium. Mohs' hardness rating of 8, but sometimes brittle.

Emerald and Diamond Ring in 14K White Gold
Emerald Ring in 10K Gold with Diamond Accents

Emerald and Diamond Wave Ring in 14K White Gold - Size 7

TIGER'S EYE

The unique appearance of tiger's eye is caused by fibrous inclusions. Light is refracted off of these inclusions giving tiger's eye its chatoyancy (changeable luster).

Yellow to yellow-orange to brown

A type of quartz. Mohs' hardness rating of 7.0

SAPPHIRE

Any color of corundum except red is called "sapphire," although cornflower blue is the most popular and sought-after sapphire color. Sapphire comes from the same places and in the same qualities as its sister stone, ruby, with the best color coming from Kashmir and Burma. The name "sapphire" alone refers to the blue variety. All other colors have the color name added to the stone, as in "orange sapphire," "pink sapphire" etc.

Sapphire often has some inclusions, but clarity is still quite good. Its base material, corundum, is the second hardest in existence and so wears very well. Often, the sapphires used in jewelry are heat-treated or given chemical diffusion to enhance their color; these enhancements are permanent. Like rubies and emeralds, there are good synthetics available for people who like the color but not the cost.

Sapphire is said to be a mind-opening gem. It is supposed to relax the wearer and clarify thought, as well as attract "divine favor." On a personal level, it prevents envy and fraud, and brings truth and good health. It also was said to be a powerful antidote for poison.

Sapphire is the birthstone of September

Blue, pink, green and yellow

The colored varieties of corundum, with the color coming from iron and titanium. Mohs' hardness rating of 9.

CRYSTAL

Crystal is created using a combination of silica (quartz sand) and natural minerals. To avoid stress and inclusions, the glass is cooled slowly.

Colorless quartz

Mohs' hardness rating of 7.

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AMETHYST

Amethyst was a valuable gem until the discovery of large deposits in South America in the late 1800s; Brazil is the primary exporter to this day, although it is common in many countries. Still, its deep and attractive color makes it extremely popular. Banding - darker and lighter zones of color - is quite common. A good amethyst will be very clear, and the deeper the color, the better. The most common enhancements are heat and irradiation. Try not to expose an amethyst to excessive amounts of bright sunlight, as this can fade its color.

Perhaps the most unusual magical power ascribed to the amethyst is its ability to prevent drunkenness. It also is supposed to bring peace of mind to the wearer, and if properly carved, prevent fatal poisoning. In some legends, it represented piety and dignity.

Amethyst is the birthstone for February.

Pale lilac to deep purple

The most precious form of quartz, amethyst receives its color from iron and manganese. Durable, with a Mohs' hardness rating of 7.

Cushion-Cut Amethyst Ring in 14K White Gold with Diamond Accents

Pear-Shaped Pink Amethyst Ring in 10K Rose Gold with Diamond Accents

ALEXANDRITE

Discovered in Russia in the early 1800s, alexandrite is named for Tsar Alexander II and was the national gemstone of tsarist Russia. With an ability to change its color from green to red depending on the light source, alexandrite is a very unique and beautiful gemstone. A Mohs' hardness rating of 8.5 makes alexandrite a very durable and trouble-free gemstone.

Green or blue-green to red or red-violet

Mohs' hardness rating of 7 to 7.5

Oval Simulated Alexandrite Earring and Pendant Set in Sterling Silver

Lab-Created Alexandrite Mini Star Pendant in 10K Gold

AGATE

Agate is formed in cocentric layers that lends itself to a multi-colored striped appearance. This ensures that no two agates are quite the same. It is often used in cameos and other fashion jewelry. Agate also is what forms the basis of petrified wood.

Multi-colored in cocentric layers

Micro-crystalline quartz (chalcedony). Mohs' hardness rating of 6.5 - 7.0.

Red Agate Gemstone Ring in 10K White Gold with Diamond Accents

Red Agate Ring in 14K Gold Vermeil

Red Agate Pendant in 14K Gold Vermeil and Sterling Silver

Red Agate Earrings in 10K Gold

Treatments applied to gemstones

Gemstones are often treated to enhance the color or clarity of the stone. Depending on the type and extent of treatment, they can affect the value of the stone. Some treatments are used widely because the resulting gem is stable, while others are not accepted most commonly because the gem color is unstable and may revert to the original tone.

HEAT

Heat can improve gemstone color or clarity. Most citrine is made by heating amethyst, and partial heating with a strong gradient results in ametrine - a stone partly amethyst and partly citrine. Much aquamarine is heat treated to remove yellow tones, change the green color into the more desirable blue or enhance its existing blue color to a purer blue.
Nearly all tanzanite is heated at low temperatures to remove brown undertones and give a more desirable blue/purple color. A considerable portion of all sapphire and ruby is treated with a variety of heat treatments to improve both color and clarity.
When jewelry containing diamonds is heated (for repairs) the diamond should be protected with boracic acid; otherwise the diamond (which is pure carbon) could be burned on the surface or even burned completely up. When jewelry containing sapphires or rubies is heated (for repairs) it should not be coated with boracic acid or any other substance, as this can etch the surface; it does not have to be "protected" like a diamond.

RADIATOR

Most blue topaz, both the lighter and the darker blue shades such as "London" blue, has been irradiated to change the color from white to blue. Some improperly handled gems which do not pass through normal legal channels may have a slight residual radiation[citation needed], though strong requirements on imported stones are in place to ensure public safety. Most greened quartz (Oro Verde) is also irradiated to achieve the yellow-green color.

WAXING/OILING
Emeralds containing natural fissures are sometimes filled with wax or oil to disguise them. This wax or oil is also colored to make the emerald appear of better color as well as clarity. Turquoise is also commonly treated in a similar manner.

FRACTURE FILING
Fracture filling has been in use with different gemstones such as diamonds, emeralds and sapphires. More recently (in 2006) "Glass Filled Rubies" received a lot of publicity. Rubies over 10 Carat (2 g), particularly sold in the Asian market with large fractures were filled with lead glass, thus dramatically improving the appearance (of larger rubies in particular). Such treatments are fairly easy to detect.

Cutting and polishing & color of gemstones

A few gemstones are used as gems in the crystal or other form in which they are found. Most however, are cut and polished for usage as jewelry. The two main classifications are stones cut as smooth, dome shaped stones called cabochons, and stones which are cut with a faceting machine by polishing small flat windows called facets at regular intervals at exact angles.

Stones which are opaque such as opal, turquoise, variscite, etc. are commonly cut as cabochons. These gems are designed to show the stone's color or surface properties as in opal and star sapphires. Grinding wheels and polishing agents are used to grind, shape and polish the smooth dome shape of the stones.[9]

Gems which are transparent are normally faceted, a method which shows the optical properties of the stone’s interior to its best advantage by maximizing reflected light which is perceived by the viewer as sparkle. There are many commonly used shapes for faceted stones. The facets must be cut at the proper angles, which varies depending on the optical properties of the gem. If the angles are too steep or too shallow, the light will pass through and not be reflected back toward the viewer. Special equipment, a faceting machine, is used to hold the stone onto a flat lap for cutting and polishing the flat facets.[10] Rarely, some cutters use special curved laps to cut and polish curved facets.

GEMSTONE COLOR is the most obvious and attractive feature of gemstones. The color of any material is due to the nature of light itself. Daylight, often called white light, is actually a mixture of different colors of light. When light passes through a material, some of the light may be absorbed, while the rest passes through. The part that is not absorbed reaches the eye as white light minus the absorbed colors. A ruby appears red because it absorbs all the other colors of white light - blue, yellow, green, etc. - except red.

The same material can exhibit different colors. For example ruby and sapphire have the same chemical composition (both are corundum) but exhibit different colors. Even the same gemstone can occur in many different colors: sapphires show different shades of blue and pink and "fancy sapphires" exhibit a whole range of other colors from yellow to orange-pink, the latter called "Padparadscha sapphire".

This difference in color is based on the atomic structure of the stone. Although the different stones formally have the same chemical composition, they are not exactly the same. Every now and then an atom is replaced by a completely different atom (and this could be as few as one in a million atoms). These so called impurities are sufficient to absorb certain colors and leave the other colors unaffected.

As an example: beryl, which is colorless in its pure mineral form, becomes emerald with chromium impurities. If you add manganese instead of chromium, beryl becomes pink morganite. With iron, it becomes aquamarine.

Some gemstone treatments make use of the fact that these impurities can be "manipulated", thus changing the color of the gem.

Value of gemstones

There is no universally accepted grading system for any gemstone other than white (colorless) diamond. Diamonds are graded using a system developed by the Gemological Institute of America (GIA) in the early 1950s. Historically all gemstones were graded using the naked eye. The GIA system included a major innovation, the introduction of 10x magnification as the standard for grading clarity. Other gemstones are still graded using the naked eye (assuming 20/20 vision).[2]

For the past several hundred years, gemstones have been broken down into two categories; precious and semi-precious. Though today we think primarily of diamond, ruby, sapphire, and emerald as "precious", these categories are based mainly on fashion and the composition of these two lists has changed frequently over time.[3]

Recently a mnemonic device, the "four C's" (color, cut, clarity and carat), was introduced to help the consumer understand the factors used to grade a diamond.[4] With modification these categories can be useful in understanding the grading of all gemstones. The four criteria carry different weight depending upon whether they are applied to colored gemstones or to colorless diamond. In diamonds, cut is the primary determinant of value followed by clarity and color. Diamonds are meant to sparkle, to break down light into its constituent rainbow colors (dispersion) chop it up into bright little pieces (scintillation) and deliver it to the eye (brilliance). This is a function of cut. In its rough crystalline form, a diamond will do none of these things, it requires proper fashioning and this is called "cut". In gemstones that have color, including colored diamonds, it is the purity and beauty of that color that is the primary determinant of quality.

Physical characteristics that make a colored stone valuable are color, clarity to a lesser extent (emeralds will always have a number of inclusions), cut, unusual optical phenomena within the stone such as color zoning, and asteria (star effects). The Greeks for example greatly valued asteria in gemstones, which were regarded as a powerful love charm, and Helen of Troy was known to have worn star-corundum.[5]

A factor in determining the value of a gemstone is called water. Water is an archaic term that refers to the combination of color and transparency in gemstones; used hierarchically: first water (gem of the finest water), second water, third water, byewater.[6]

Historically gemstones were classified into precious stones and semi-precious stones. Because such a definition can change over time and vary with culture, it has always been a difficult matter to determine what constitutes precious stones.[7]

Aside from the diamond, the ruby, sapphire, emerald, pearl (strictly speaking not a gemstone) and opal [7] have also been considered to be precious. Up to the discoveries of bulk amethyst in Brazil in the 19th century, amethyst was considered a precious stone as well, going back to ancient Greece. Even in the last century certain stones such as aquamarine, peridot and cat's eye have been popular and hence been regarded as precious.

Nowadays such a distinction is no longer made by the trade. [6]

Many gemstones are used in even the most expensive jewelry, depending on the brand name of the designer, fashion trends, market supply, treatments etc. Nevertheless, diamonds, rubies, sapphires and emeralds still have a reputation that exceeds those of other gemstones.

Rare or unusual gemstones, generally meant to include those gemstones which occur so infrequently in gem quality that they are scarcely known except to connoisseurs, include andalusite, axinite, cassiterite, clinohumite and bixbite.

Gems prices can fluctuate heavily (such as those of tanzanite over the years) or can be quite stable (such as those of diamonds). In general per carat prices of larger stones are higher than those of smaller stones, but popularity of certain sizes of stone can affect prices. Typically prices can range from 5USD/carat for a normal amethyst to 20,000-50,000USD for a collector's three carat pigeon-blood almost "perfect" ruby.

GEMSTONE

A gemstone or gem, also called a precious or semi-precious stone, is a piece of attractive mineral, which — when cut and polished — is used to make jewelry or other adornments.[1] However certain rocks, (such as lapis-lazuli) and organic materials (such as amber or jet) are not minerals, but are still used for jewelry, and are therefore often considered to be gemstones as well. Most gemstones are hard, but some soft minerals are used in jewelry because of their lustre or other physical properties that have aesthetic value. Rarity is another characteristic that lends value to a gemstone.