All weights pertaining to gemstones, including diamonds, are minimum weights. Additionally, please note that many gemstones are treated to enhance their beauty. View Gemstone Enhancements and Special Care Requirements for important information.
Although gold is most often thought of as having a soft, yellow glow, the metal is available in an entire spectrum of different hues. The different colors of gold depend upon with which metals the gold is alloyed, or mixed.
Increasing in popularity in recent years, white gold has become fashionable as the preferred cool and contemporary look. White gold boasts the same properties as classic yellow gold, but achieves its white color by mixing with different alloys. In general, white gold is created when a nickel or palladium alloy (zinc and copper) is used. White gold may also be plated with an even whiter metal, such as rhodium, to enhance its cool appearance. As well, a white gold setting can enhance the rapture of white diamonds.
Gold's softness and malleability make it a wonderful metal to work with when creating virtually any design in jewelry. But this softness can be a drawback as well. To make it stronger and more durable, gold is usually alloyed, or mixed, with other metals such as copper or silver. The higher a metal's percentage of gold content, the softer and more yellow the jewelry piece. The karat weight system used to measure gold in a piece is the same for all hues, including white and yellow gold.
The word “carat” is Arabic, meaning “bean seed.” This is because historically seeds were used to measure weights of gold and precious stones. In the United States, “karat” with a “k” is used to measure gold's purity, while “carat” with a “c” is used in measuring a gemstone's size. The karat mark of gold represents the percentage of pure gold to alloy.
In order to determine the karat weight of a specific item, simply look for the quality mark. Jewelry items will bear the stamp of their karatage based upon the United States or European system of marking. The United States system designates pieces by their karats—24K, 18K, 14K, 10K, etc. The European system designates pieces by their percentage of gold content. For instance, 10K gold is marked “417,” denoting 41.7% gold; 14K is marked “585,” denoting 58.5% gold; and 18K is marked “750,” denoting 75% gold; etc.
Amethyst, the most precious member of the quartz family, exhibits purple shades ranging from pale lilac to deep purple, sometimes exhibiting reddish or rose overtones. Very deep-colored amethysts are the finest and most highly valued . Some stones are so over-saturated with color they have areas that are blacked out, which can negatively impact their value. Paler shades, sometimes called "Rose of France," were common in Victorian jewelry. Banding—darker and lighter zones of color—is also a common occurrence. Occasionally, amethyst is even found combined with its sister quartz, citrine, into a single stone called ametrine.
The birthstone for February, amethyst is an extremely popular gem for jewelry because of its regal color, variety of sizes and shapes, affordability and wide range of hues. It also is the recommended gem for couples celebrating their 6 th and 17 th wedding anniversaries. With a hardness of 7.0 on the Mohs Scale , a methyst can occur as long prismatic crystals that have six-sided pyramids at either end, or can form as drusies that are crystalline crusts that only show the pointed terminations.
The ancient Greeks believed that amethyst made one immune to the effects of alcohol. In fact, the name even comes from the Greek word amethystos, which means “not drunken.” Legend has it that the amethyst originated from Bacchus, the god of wine. Bacchus became angry at the mortals and vowed that the next mortal to cross his path would be eaten by tigers. Amethyst, a beautiful young maiden, was on her way to worship the goddess, Diana. Diana turned her into colorless quartz to keep her from being eaten. Bacchus observed the miracle and repented his hasty decision. He poured wine over the young maiden, leaving her feet and legs colorless. This is the reason that amethyst crystals are usually uneven in color and have a colorless base at the bottom. Because amethyst was believed to prevent drunkenness, wine goblets were often carved from it in ancient Greece. Today, the gem still symbolizes sobriety.
Amethyst has been a part of history throughout the ages. Evidence suggests that prehistoric humans used amethysts for decoration as early as 25,000 B.C. Legends suggest that the Egyptian queen Cleopatra wore an amethyst signet ring, as did Saint Valentine, who bared an amethyst engraved with the figure of Cupid. During medieval times, people used the stone as medication to stay awake and alert. Leonardo Da Vinci claimed that amethyst could dissipate evil thoughts and quicken the intelligence. In some legends, the stone represents piety, celibacy and dignity. In the Middle Ages, for instance, the gem was an important ornamentation for the Catholic Church and other religions. It was considered the stone of bishops, and they still often wear amethyst rings. In Tibet, amethyst is considered sacred to Buddha and rosaries are often made from it. Amethyst has also long been a favorite of kings and queens for its royal purple hues that symbolize wisdom, strength and confidence. Amethysts are even featured in the British Crown Jewels and were worn by Catherine the Great.
Amethyst’s availability and magical qualities make it the stone of preference in ancient lore and mysticism. As a meditation stone, it is said to quiet the mind, promote contemplation, sharpen psychic powers and uplift the spirit. It is a stone of deep wisdom. Folklore says it can quicken the wit, calm fears and ward off anger. It has a royal purple essence that is said to lend courage to travelers, scare off thieves and protect travelers from harm. Placed under the pillow or worn to bed, there are claims it promotes peaceful sleep and pleasant dreams. Amethyst can also be worn to supposedly make the wearer gentle, amiable and happy.
The stone is mined in Brazil, Uruguay, Bolivia and Argentina, as well as in Zambia, Namibia and other African nations. Very dark amethyst in small sizes also is mined in Australia. But the ideal for fine quality amethyst was set by a Siberian variety, often called Russian or Uralian amethyst, which is now considered a defunct source. Generally, South American amethyst tends to come in larger sizes than African amethyst, but the African variety has a reputation for having deeper color intensity and is therefore considered more valuable. The African version also is harder to come by than amethyst mined from South America. Most of today's amethyst comes out of Brazil.
Lune de France is a very special variety of amethyst that rarely comes to market. From the northwest state of Amazon in Brazil, this gemstone comes from the Maraba mine. This lovely lilac gemstone features a unique velvet-like quality that at first observation can be confused for an opal or moonstone. The gemstone's internal structure contains natural, cloud-like veils of microscopic inclusions that are extremely minute, even under high power magnification. These inclusions cause the incoming light to scatter and reflect, thus creating an opalescent effect. While a similar inclusion structure can be expected in rose quartz, it almost never occurs in an amethyst. Lune de France features a natural lilac color and retains excellent transparency allowing it to be faceted for maximum light play.
Iolite gets its name from its sensational color, using the Greek words ios (violet) and lithos (stone). The stone, often referred to as water sapphire, cordierite or dichroite, was used by the Vikings as a navigational tool and came to be known as “Vikings’ Compass.” When Viking explorers ventured far into the Atlantic Ocean, away from any coastline that could help them determine position, they were able to navigate safely by looking through iolite lenses that allowed them to find the exact position of the sun.
The property that made iolite so valuable to the Vikings was the gem’s pleochroic property, which is the display of different colors when viewed from different directions (like a modern-day polarized filter used in sunglasses). A cube cut from iolite will look violet-blue from one side, clear as water from the other and honey yellow from the top.
Pleochroism may have been helpful in navigation, but it makes a gem cutter’s job quite difficult. If iolite is not cut from exactly the right direction, its color will not show to its best advantage. When cut properly, the stone is usually a violet blue and can be obtained in sizes up to 5.00 carats relatively easily. Iolite ranks a 7.0-7.5 on the Mohs Scale and is readily available and affordable. Today, it is mined in Brazil, India, Mozambique, Sri Lanka and Zimbabwe. The Vikings probably mined iolite from deposits in Norway and Greenland.
Traditionally given as a 21 st anniversary gift, iolite is thought to bring harmony to relationships. It is also said to balance the masculine and feminine aspects of one’s own character, bringing harmony and enabling that person to enjoy each moment. Iolite is believed to heighten psychic abilities by aiding and encouraging people along their spiritual paths. It is said to enhance curiosity and achievement, and aid in money management. Iolite is also believed to possess the power to guide lost sailors to the brilliance of the sun, so that they may find their way home.
Peridot features a lively yellow-green color that is transparent with an oily luster. The iron that creates peridot’s color is an integral part of its structure, so the gem is only found in various shades of green. It is most prized in lime hues, but Italian peridot is a rich olive color and popular American peridot is a beautiful light yellow-green. The Romans called peridot “evening emerald” because its exquisite green color was said to glow at night. This is perhaps because the stone exhibits double refraction, meaning that when looking through the stone, objects appear double. So when looking into a faceted peridot, the number of bottom facets appears to be double the actual number, creating a glittering sensation.
Pronounced PEAR-A-DOE, the word “peridot” comes from the French word meaning “gem.” It is the gem variety of the mineral olivine and ranks a 6.5-7.0 on the Mohs Scale.
Born in cauldrons of fire, peridot is considered the “volcanic gem,” since small crystals of it are often found in the rocks created by volcanoes. In fact, Hawaiian legend called peridot the divine tears wept by Pele, goddess of the volcano. The island of Oahu even has beaches made out of olivine grains, but they are much too small to cut into peridot. Samples of the gem also have been discovered in meteorites that have fallen to Earth, many of which are more than a billion years old.
Peridot traces its jewelry roots to 3,500 years ago. The stone was first mined by the ancient Egyptians on the volcanic island of Zebargad in the Red Sea. Known as the “serpent isle,” it was infested with poisonous snakes that interfered with mining activity until one Pharaoh had them all driven into the sea. Today, Native Americans mine most peridot on the San Carlos Reservation in Arizona. Interestingly, a lmost all peridot sold in Hawaii is from Arizona, despite the fact that peridot is produced by Hawaii's volcanoes. The gemstone is also found in Norway, Brazil, China, Egypt, Italy, Myanmar and Sri Lanka. An exciting new deposit was discovered in Pakistan in 1994, yielding some of the finest peridot ever seen, including one stone that weighed more than 300.00ct.
Peridot is among the oldest known stones and has been mined as a gem for thousands of years. As early as 1575 to 1350 B.C., the ancient Egyptians used peridot beads in their ceremonial jewelry. In fact, it is believed the stone was one of the favorite gems of Cleopatra and that some of the “emeralds” she wore were actually peridot.
Ancient Egyptians also carved small drinking vessels out of large chunks of peridot. Priests would drink soma from them in rituals, believing the soma would put them in touch with the nature goddess, Isis. Legend has it that King Soloman traded cedar trees from Lebanon for 12 soma drinking cups and 144 liters of soma. The Egyptians made this trade for ramp logs to build their pyramids at Gisa, while King Soloman was said to have been enlightened by drinking soma from the peridot cups. Today, Mexican hill tribes still drink soma from green glazed cups to put them in touch with nature and their ancestors’ spirits. Additionally, some Native American Indians in Arizona use tea made from peyote ground with peridot crystals in their rituals.
Peridot has also been important to other cultures throughout history. Late in the Ottoman Empire (1300 to 1900), peridot was a highly prized gem and Turkish Sultans amassed some of the world’s largest collections of the gemstone. It is mentioned in the Bible under the name of “chrysolite,” and was used to decorate medieval churches with samples that were most likely carried back to Europe by the Crusaders. Large stones weighing more than 200.00ct adorn the Shrine of the Three Magi at the Cologne Cathedral in Germany.
Throughout the ages, peridot has been believed to hold mystical powers of protection and healing. The ancients regarded the stone as a symbol of the sun and wore it in amulets to prevent nightmares and drive away evil spirits. It was even favored by pirates to protect them against evil. Peridot was said to be useful for calming raging angers, curing nervous afflictions and promoting quiet sleep. It was also believed to strengthen any medicine drunk from goblets carved from the stone. South American Shamans used peridot to ward off snakebites and the evil spirits who have taken the form of mosquitoes who bring the sleeping sickness. They also say the heating of magic mushroom tea by peridot takes them on trips to the ancestor heavens.
Today, peridot is believed to bring the wearer success, peace and good luck. To be most powerful, it is said that the stone should be mounted in gold and surrounded with small diamonds. With powers that are thought to bring protection and health, modern folklore also says it can be used to attract love and calm anger while soothing nerves and dispelling negative emotions. T he gem is believed to protect the wearer from bad dreams when set in gold.
Peridot is considered the birthstone of August. Given as a symbol of fame, dignity and protection, this gem is also traditionally given to couples celebrating their 16 th wedding anniversaries.
A symbol of strength and intelligence, topaz derives its name from Topazios, an island in the Red Sea that is known today as Zabargad. The Greek word “topazios” means “to seek,” since the island was covered with a thick fog and difficult to find. Gemstones found on the island were called topaz, although the stones were eventually found to actually be peridot. The real gem of topaz is found throughout the world, with different occurrences producing specific colors.
Brown, yellow, orange and red topaz are found in Brazil, Sri Lanka and Siberia. Most brownish topaz is heated to produce a permanent and glamorous pink color. Following the discovery of pink topaz in Russia during the 19th century, Imperial topaz was found. Featuring a sherry red, deep pink or reddish-orange color, the gem was so coveted that its ownership was restricted to the Czar, his family and those who received it as a royal gift. Today, Imperial shades are the most rare and, therefore, the most valuable.
Blue topaz is rarely found in nature and is most often created through a combination of heat treatment and irradiation. It is found in Brazil, Sri Lanka, Nigeria and China. Topaz is often colorless, too, and can be found in the United States, Mexico, Russia and Pakistan. In 1998, a new type of enhanced topaz made its appearance with a greenish-blue or emerald green color. All colors of topaz rank an 8.0 on the Mohs Scale of hardness.
Yellow topaz is November’s birthstone and blue topaz is December’s birthstone. Blue topaz is also the traditional gift for 4th and 19th wedding anniversaries, while Imperial topaz is celebrated as a 23rd anniversary gift. Perhaps the most famous topaz is a large, colorless stone known as the Braganza. It was discovered in Brazil in 1740 and was originally thought to be a priceless diamond. Today, the giant 1,680.00ct stone is set in the Portuguese Crown.
The mystery and allure of topaz goes back thousands of years. To the ancients, it was a symbol of love and affection and was thought to ward off sudden death. The Romans associated topaz with Jupiter, the god of the sun. The Greeks called it the Stone of Strength, believing it had the power to increase strength and make its wearer invisible in times of emergency. The Egyptians said the gem was colored with the golden glow of the sun god, Ra, making topaz a powerful amulet that protected its wearer against harm.
Topaz' mystical curative powers were believed to wax and wane with the phases of the moon. The gem was said to change color in the presence of poisoned food or drink and falcons were carved on the stones to help earn the goodwill of kings and magnates.
Today, topaz is said to be the gem that has the widest range of curative powers. It is believed to dispel enchantment and protect against negative emotions such as anger, fear, greed and envy. Its properties are supposedly enhanced when the gem is mounted in gold. Because of this association with gold, topaz is used to bring or enhance the wearer's money-gathering abilities and has long been used in money and wealth rituals.
Wearing topaz is said to improve and deepen relationships, promote patience, ensure fidelity and enhance the ability to love. The gem is also believed to bring friendship, intelligence, long life, beauty and a pleasant disposition.
Chrome diopside, also called Russian diopside, offers an intense forest green color. Because it is the most affordable gemstone with a pure, rich green color, many jewelry designers predict chrome diopside will be the world’s leading emerald substitute by the end of the decade. It is mostly available in smaller sizes, with the rare larger sizes becoming much more expensive and too dark. A 26.17ct oval cut chrome diopside may be the largest known example of the faceted stone, but there is also a 25.33ct stone that is brighter and more intense in color.
Chrome diopside is relatively soft, with a hardness of 5.5 on the Mohs Scale. Mostly mined in Yakutia and Siberia, the liberalization of the former Soviet Union's economy has made chrome diopside more available, and more popular, than ever before.
Garnet comes in a vast rainbow of naturally exquisite hues, occurring in every color except blue. It is the family of minerals that displays the greatest variety of colors than any other mineral. The eight major types of garnets include almandine, pyrope, demantoid, grossularite, tsavorite, hessonite, rhodolite and spessartite.
Named after the ancient gemstone city of Alabanda in Asia Minor, the most common type of garnet is almandine (also called almandite). It is a dark red to brownish red stone that is only slightly different from the chemical structure of its sister stone, called pyrope. While nature only grows pyropes in small sizes, it allows for almandine crystals to form in larger dimensions.
Pyrope is a high-quality garnet that can be purplish red, blood red, orange-red or crimson. It is often called the Bohemian garnet since its fierce and often slightly bronze color was highly popular in the 18th and 19th century when it came from the north-eastern part of the former Kingdom of Bohemia. In Europe during the Victorian times, pyrope garnets frequently decorated jewelry with many of these small stones tightly arranged along each other like the seeds of a pomegranate. In fact, the name “garnet” most likely was derived from the pomegranate, a fruit whose deep, red-purple color resembles some varieties of the gem. Many ancient pieces of garnet jewelry are also studded with the tiny red gems.
Demantoid is a rich green variety of garnet primarily found in the Ural Mountains of Russia. Russia’s leading court jeweler, Carl Fabergé, loved this brilliant garnet more than any other stone and used it in many of his creations that were lavishly adorned by the Tsars of Russia. Today, demantoid is appearing more often in the gemstone market because of new finds in Namibia. However, these particular garnets from Namibia lack "horsetail-inclusions,” the fine bushy-shaped inclusions that are characteristic of the sought-after Russian demantoids. The gem is quite rare and can cost several thousand dollars per carat depending on size and quality. The larger, brighter demantoid s are exceedingly scarce and have been known to show exceptional brilliance, even higher than diamonds.
Grossularite, available in pinks, browns, greens and yellows, is especially cherished because of its many in-between shades and earth colors. In the last year of the 20th century, large grossularite occurrences were discovered in Mali. Charming because of their high brilliance, the Mali garnets make even the brown color attractive and vivid.
Tsavorite is the trade name for a fine green grossularite. It ranges from vivid light green to velvety deep green and, like all other garnets, features a strikingly high brilliance. Tsavorite was discovered in 1967 by British geologist Campbell R. Bridges, and was re-named by Tiffany’s in New York after its occurrence near the famous game park Tsavo-National Park. Mined in Tanzania and Kenya, this particular stone is quite rare and can cost several thousand dollars per carat depending on size and quality. Larger tsavorites are exceedingly scarce.
Hessonite is the variety name for a fine orange, cinnamon brown or pinkish variety of grossularite. It most commonly occurs in golds, oranges and browns.
Rhodolite is a pyrope-almandine garnet that features a velvety red color with a fine purple or raspberry colored undertone. One of the most popular varieties, it is mined in East Africa, India and Sri Lanka and was originally discovered in the United States.
Spessartite garnet can be red or blackish brown, but is most commonly available in golds, oranges and warmer browns. Originally named after its occurrence in the German Spessart Mountains, there was a surprising discovery of the bright orange-red stone in Nigeria and Namibia. Until then, spessartites had existed as mere collector’s items or rarities and were hardly ever used for jewelry because they were so rare. But the new location discovery changed the world of jewelry gemstones and spessartites made their way into jewelry fashion. The most popular type of spessartite is the mandarin garnet, a gem that features a bright orange hue.
Traditionally given as 2nd wedding anniversary gifts, garnets are celebrated as January’s birthstone. They are found all over the world, including Africa, Australia, Eastern Europe, the Middle East, North America, South and Central America, and Southeast Asia. The garnet ranges from 7.0-7.5 on the Mohs Scale and has been given many different names throughout the gemstone trade, including Arizona Ruby, Arizona Spinel, Montana Ruby or New Mexico Ruby. The stone features a high refraction of light that creates an amazing brilliance and luminosity. In fact, Noah used a garnet lantern to illuminate the darkness and navigate the Ark through 40 days and nights of torrential rain.
Throughout history, garnets have been widely known and prized for their rich hues and supposed mystical properties. Adored by the ancient Egyptian goddess Isis, the gem symbolized faith, truth and friendship and was a favorite of Egyptian jewelry artisans. Garnets were taken into the tombs with the dead as payment to the gods for safe passage through the nether world. It is said that King Solomon wore a large red garnet along with eleven other magical gems in his breastplate (representing the 12 steps of Jacob's Ladder) to help him win battles. Nineteenth-century Asiatic warriors even used the hard stones as bullets. In the 13th century, medieval travelers wore garnets as popular talismans and protective stones, many of which were carved with lions. The gems were thought to repel evil spirits, bad dreams and people with evil intent.
Today, garnets are thought to have protective powers and can be carried by travelers to protect against accidents. The stone is said to light up the night and protect its owner from nightmares. It is also believed to strengthen the body and mind by sparking creativity and dispelling anger. People may use the stone to increase the power of their energy fields and gather good vibes. Current superstitions say that the stone symbolizes loyalty and can be exchanged between friends to symbolize affection and ensure they meet again.
No other gemstone discovery has made a bigger impact on the jewelry market than the recent newcomer, tanzanite. Its luscious color, and the fact that the stone is found in only one location throughout the world, makes tanzanite an exceptionally rare, valuable and highly sought-after gem.
Tanzanite’s mesmerizing saturation of color is what has made the stone so popular. It is the blue variety of the mineral zoisite and occurs in a beautiful range of colors. Rarely pure blue, the gem almost always displays signature overtones of purple. In smaller sizes, it tends toward light tones such as lavender, while in larger sizes, the gem typically displays deeper, richer blues and purples. The finest quality tanzanite is usually deep blue or violet, which is extremely spectacular in sizes above ten carats.
Tanzanite is pleochroic, meaning it shows the appearance of several colors in the same stone, depending on perspective. From different angles, the gem can appear blue, purple, yellow, grey or brown. Most rough crystals show a large proportion of brown shades, since tanzanite in its natural form is typically brown with red, orange, yellow or bronze hues.
Gem cutters may change this coloring by heating the stone to 500°C. This heat treatment releases the intense violet-blue colors for which the stone is famous. According to legend, the effect of heat on tanzanite was first discovered when brown zoisite crystals were caught on fire by a lightning strike. Local cattle herders noticed the beautiful blue crystals sparkling in the sun and picked them up, becoming the first tanzanite collectors.
The gem was first discovered near the base of Mount Kilimanjaro in the Merelani Hills of east-African Tanzania in 1967. This breathtaking location is the only known mining site on Earth for tanzanite. Right after its discovery, New York jeweler Louis Comfort Tiffany was presented with the first stones. Knowing it was going to be a sensation, he recommended finding a new name for the gem, since the gemological denomination “blue zoisite” reminded him of the word “suicide.” Tiffany suggested the name tanzanite, derived from its place of occurrence, and the new name quickly became established on the market. Tiffany & Co introduced the stone to the public in a spectacular promotional campaign two years after it had been discovered. It was enthusiastically celebrated as the “Gemstone of the 20th Century.”
A noted 122.70ct faceted tanzanite dubbed the “Midnight Blue” is on display at the Smithsonian Institution in Washington, D.C. In 1996, a 255.00ct tanzanite crystal was discovered near Arusha, but because of its many inclusions, it proved to be of little market value. Tanzanite ranks a hardness of 6.5-7.0 on the Mohs Scale and has become the traditional gift for couples celebrating their 24th anniversaries.
High-quality and larger-size tanzanites can be sold at extremely premium prices. Although demand for this beautiful gem continues to grow, supply shortages in recent years have hampered production and caused price fluctuations. In 1998, the weather phenomenon known as “El Nino” soaked Tanzania with heavy rains during what should have been the drought period. When the monsoons hit, the groundwater swells were high and caused devastating floods. Mines caved in and all hopes of finding additional tanzanite rough were swept away.
Because it is such a new gemstone, there is little folklore, superstitions or healing properties surrounding tanzanite. Some believe the stone helps people to be more practical, realistic and honest. It is thought to uplift and open the heart while helping one cope with change.
The name apatite comes from a Greek word "apatos," meaning deception, which alludes to the mineral's similarity with other more valuable minerals such as olivine, peridot and beryl. It can be transparent to opaque, with color that is typically green but can also be yellow, blue, reddish brown, violet and colorless. This gem exhibits an unusual "partially dissolved" look similar to the look of previously sucked-on hard candy.
Apatite is widely distributed in all rock types, but is usually just found as small grains or fragments. Large and well-formed crystals, though, can be found in certain contact metamorphic rocks; but with a hardness of 5.0 on the Mohs Scale, the softness of apatite prevents wide distribution in the jewelry market. Apatite occurs generally in rather rough prismatic crystals, the largest being 4 inches long and 1 inch in diameter.
In most limestone quarries, careful search shows the presence of small prisms of bright green apatite in the limestone. Notable occurrences include Germany, Brazil, Russia, Myanmar (Burma), Sri Lanka (Ceylon), Canada, East Africa, Sweden, Spain and Mexico.
Earring Back Types
Butterfly Back: A double looped piece resembling a butterfly that fits over a post. Variations on this design are called push back clasps. The basic post and butterfly back are usually used for stud earrings and lighter weight drop earrings.
Hinged Snap Backs: This clasp features a hinged post that snaps into a groove on the back of the earring. It is commonly found on hoops. Sometimes the hinged post is curved to provide more room to fit around the ear, sometimes called a saddleback.
Hook Backs: This earring backing is simply a long, bent post that fits through the piercing. Hooks have several variations, most notably the shepherd's hook and the French hook. While thin wire hooks reduce the weight of long earrings, making them more comfortable, they aren't as secure as other clasp styles.
Lever Back: A hinged lever snaps shut against the curved post to form a closed loop around the ear lobe. This clasp is very secure and good for large or medium sized styles that drop just below the ear.
Omega: Also called French clips, this clasp has a straight post and a looped lever. The hinged lever closes around the post and is held against the ear with pressure. The omega clasp is the most secure clasp, especially for the larger, heavier earrings.
Screw back: This backing is a slight variation of the standard post and butterfly nut back. Instead of pushing on the back, the nut twists onto the threaded post. A screw back post design is often preferred for expensive diamond stud earrings that require increased security.