Opalescence effects in Opal

    Opalescence effects in Opal

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    Opalescence effects in Opal

    by Nasrina Parvin Khan

    The milky, turbid aspects of opal described as opalescence. This phenomenon has been seen in common opal or potch opal. These types of opal do not show a play of color.

    There are various kinds of special optical phenomenon, which can be exhibit by the gems. Special optic phenomenon is the unique property of a gem that adds a distinct identity character to the gem. We can identify the gem with this property. Sometimes a particular type of gem shows multiple special optical phenomena, like opal.

    We know opal for its play of color. Except play of color, opal exhibits another special optical phenomenon named opalescence.

    opalescenceUsually, people confused with two special optical phenomena in opal. But play of color and opalescence are two different phenomenon of opal.

    The milky, turbid aspects of opal described as opalescence. This phenomenon has been seen in common opal or potch opal. These types of opal do not show a play of color.

    The term ‘opal’ derives from the Greek ‘opallios’, the Latin ‘opalus’ and the Sanskrit ‘upala’ that means precious stone.

    The ranges of color in opal may vary from colorless to white, milky blue, gray, red, yellow, green, brown and black.

    Opalescence – How it happen?

    Opalescence is caused by the reflection of short wavelength light. Usually it occurs in the blue spectrum. Due to this action of light a milky blue, pearly appearance occurs in opal which known as opalescence.

    The structural pattern of opal is the reason of this special optical phenomenon thus the reflection of short wavelength.

    Opal is an amorphous form of silica (SiO2, nH2O). It is made up of sub-microscopic spheres of silica with a little amount of water. Air also trapped in the spaces between these round spheres. The amount of water in opal may 3% to 21%.

    In case of common opal, the openings between the spheres are comparatively large. So, the light doesn’t have to bend when traveling through them and no diffraction can takes place. But the light scattered instead of diffraction. The scattering effect of light creates a sort hazy effect in the inner particles of opal, which is commonly known as opalescence.

    This phenomenon is best admired in a flat cabochon-cut opal (a tall, domed shape gem is called as cabochon). The whole surface of opal exhibits opalescence in this case.

    Opalescence Types

    We can divide opals in various types according to the color and opalescence type, such as i) white opal with opalescence against the pale gray or pale blue background, ii) black opal with effective opalescence and dark background, iii) harlequin opal with spectacular fancy opalescence outline against different colors of mosaic figures, iv) flaming opal of yellow or red color with spectacular opalescence consisted a fire.

    Opalescence is the optical phenomenon, which adds value to the opal and helps the gem belong to the royal family.

    Other Optical Effects in gemstones
    Asterism
    Play of Color
    Chatoyancy
    Labradorescence
    Adularescence
    Color Change phenomenon
    Special Optic Phenomena

    Facts about coral

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    Facts about coral

    by Binashaji

    Found as early as 6000 B.C. archaeological discoveries have found several pieces of coral used in the sixth century, perfectly preserved. These gemstones though delicate, have a long life and don’t change color even after several decades, if kept in good conditions.

    Unbelievable beauty underwater – ask anyone who has been lucky enough to go scuba diving near a Coral reef. Corals, take a long time to form. Coral reefs, are built by algae which live inside the coral polyps. These tiny creatures take millions of years to create the coral reefs, building on top of the skeletons of old coral polyps. Corals grow in a tree-like formation under the ocean in shallow waters and can grow up to one foot in height and a maximum of two inches in width. Due to erosion, many caves and crevices are naturally formed into the Reefs. These Reefs have given rise to an underwater cache of marine life. Small sharks, crabs, schools of fishes in gorgeous colors and sizes, sea urchins, eels, water snakes – a veritable treasure trove of marine life.

    CoralThere are hundreds of Coral species. Many of them, Euphyllia Torch Coral, Mushroom Corals, Star Polyp Corals, Flower Corals to name a few are cultured by hobbyists, who want to grow corals at home in large tanks. These corals are sold over the Internet also. Marine scientists are still discovering new corals, which grow at depths below 800 feet. Corals, which comprise chiefly of Calcium Carbonate, grow in shallow, warm waters, which allow the sunlight through to help in Photosynthesis. But certain types of Corals have been found in cold water also.

    Although Corals are found in many parts of the Globe, indiscriminate coral harvesting, pollution, global warming, underwater mining, cutting down of forests have all contributed to the damage to the delicate coral reefs. These reefs maintain an important ecological balance in marine life. Many countries now have regulations against breaking and smuggling of corals outside the country, to help save the Coral reefs.

    From pinkish red to deep blood red, corals grow in a variety of colors including Gold.
    Red Coral, also called Fire Coral is the one of the five corals normally used to make Jewellery. Harvested from under the ocean, this Coral has found mention in the history of most coastal regions of the Globe- India, Hawaii, Atlantic, Brazil, Italy, to name a few of the countries (over 60) in which Coral is found. Coral is one of the few gemstones that are organic (made by nature) along with Pearls and Amber. Black, White and Blue Corals, which are rare, are also used to make Jewellery. These corals are almost extinct and authentic pieces command a high price in the market.

    Found as early as 6000 B.C. archaeological discoveries have found several pieces of coral used in the sixth century, perfectly preserved. These gemstones though delicate, have a long life and don’t change color even after several decades, if kept in good conditions. They measure 3.5 on the mohs scale, meaning these gems have to handled with great care. Coral is brittle, scratched easily and can chip off or even break if handled roughly.

    While corals of the normal red variety are easily available and are economical, red corals from the Mediterranean are very highly priced – these corals are a deep attractive red and the Mediterranean coral reefs are almost extinct, making them rare. Good quality Corals have an even coloring and do not have any striations or holes in them. Imitation Corals are aplenty – dyed glass, plastic, shells and even heat-treated coral powder is passed of as authentic coral. Corals are opaque and sometimes, colored wax is filled into holes to give the coral a more dense red color. Genuine Coral Jewellery is expensive – if it is cheap, it is probably an imitation. It is always a good idea to buy coral from a reputed store.

    There are many legends surrounding this fiery stone. The Indians have given this red stone a great deal of importance. Its powder and even coral ash has the power to heal and is used in many Ayurvedic medicines. In Indian Astrology, wearing the stone as a ring or a bracelet or even as a necklace is said to ward of the negative influence of the Mangal graha (or the Planet Mars), which leads to weak constitution, high blood pressure etc. It is believed the wearer of the coral stone will be bestowed with physical and mental energy, increased lifespan, marital happiness and youth. Indian Astrologers believe that Yellow rays can regenerate cells of the body. The Coral has a very high number of Yellow rays (which are visible under a Prism) and thus, it can heal maladies of the flesh- rheumatism, genital problems and even mental disorders. Wearing a Mangal (Coral) stone is recommended if your astrological charts show a weak Mangal graha.

    Even the Greeks have a legend about corals. It is believed that the stone gets it red color from the blood of the head of the slain, snake haired Medusa – who turned men into stone. The Romans wore it as an amulet around their necks during wars as protection. The Tibetans believe that deep red coral is a healing stone. Carved coral Buddha’s, Jewellery and prayer beads are highly valued and used even today. You may have heard about the Oracles in Greek mythology- the Oracle lived in a dark cave and foretold the future- specially at important events. Kings and Queens sought the decision of the Oracles, who used corals to forecast the future. Discovery of corals on ancient Crucifixes, statues, caskets and many other articles have proved that coral has enchanted man for millions of years.

    Before Corals are polished, they appear dull and need to be sorted out for the good, big pieces, which can be made into Jewellery. Inside the ocean, they appear like trees and for many years, it was believed that Corals were actually marine trees, till research proved that Corals actually comprised of tiny living creatures! Coral Jewellery is popular both among the Fashion worshippers and followers of religion.

    Corals Combine them with pearls, set a large coral in gold or just wrap a strand of beads around your neck, the touch of coral will make you glow. Whether you want to please the planet Mangal to give you strength and vigour or you want to see the envy in your neighbor’s eye, Coral Jewellery can accomplish both tasks with equal dexterity.

    Coral Jewellery

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    Coral Jewellery

    by Binashaji

    If you love bright colors, then Coral is the perfect gem for you. Available in colors from pinkish red to a deep blood red, coral Jewellery is sure to catch your eye. A Bracelet, a ring or even earrings – splurge and pick up an entire ensemble.

    Neptune’s Gift. The coral is a mysterious gem with magical powers attributed to it. The Indians believe wearing a Coral will ward off the negative effects from the Mangal Graha. Coral powder and ash is used in making Ayurvedic medicines. The Tibetans also carve Buddha’s, Prayer Beads and charms from this gem – the red firestone will help protect them from evil. Even the Greeks and the Romans have used this stone to adorn rings, caskets, tiaras etc. Since the sixth century, Corals have fascinated mankind with their passionate Red color.

    coral beadsIf you love bright colors, then Coral is the perfect gem for you. Available in colors from pinkish red to a deep blood red, coral Jewellery is sure to catch your eye. A Bracelet, a ring or even earrings – splurge and pick up an entire ensemble. The color of coral can add a dash of zest to every outfit for every occasion. Natural red corals, Black Corals, Blue corals and White corals are among the most expensive. Red corals are more easily available than the others.

    Corals, in the recent times have become very rare. The authentic pieces command a high price. Natural deep red corals without any flaws like fissures or bands around them are also expensive. If you are being offered corals at an unbelievably low price, they stones are probably manmade or imitation. Good quality Corals have an even coloring and do not have any striations or holes in them. Genuine Coral Jewellery is expensive – if it is cheap, it is probably an imitation. It is always a good idea to buy coral from a reputed store since it is hard to differentiate the genuine pieces from the imitations.

    coral necklaceGift someone celebrating their 35th anniversary, a set of coral rings. One for him and one for her. Yes! Men can wear coral rings too – a big stone set in a square design will complement dark suits with aplomb. Before you make a purchase of Coral Jewellery, you must have some knowledge about this gemstone. There are many imitation corals available -dyed glass, plastic, shells and even heat-pressed and resin treated coral powder is passed of as authentic coral. While buying corals rings, let the length of your fingers and hands decide what will suit you the best. Try on different shapes set in various settings before deciding on a ring. The size should be perfect and the stone should be firmly set in the ring. Corals can be combined with other gems also depending on the colors you like – Pearls, Turquoise, Lapis Lazuli – the choice is varied. A coral stone set in Gold, Silver or Platinum will be an investment in Jewellery you will never regret.

    So, now that you have a beautiful Coral Ring, a Coral Bracelet will be a gorgeous addition. Fiery red, catching the light with a tilt of an elegant wrist, a Coral bracelet can make you the center of attraction. The red of the corals is a perfect foil for both light and dark colors. Bracelets too, should fit the wrist correctly, check the clasp regularly and gently tap the stones to ensure they have not become loose. Small corals can be set all along the band of the bracelet or it could be several medium sized stones set apart or even corals combined with other gems. Whether you want to create an entire ensemble or just a unique piece, Corals are the perfect for every occasion.

    Coral necklaces can make you look bright and with the variety of designs available, it is difficult to resist the lure of the Red. Long chains with coral beads, or twisted strands with corals and pearls (both organic, both from the ocean), or even a choker with corals and turquoise set in gold or silver. Several varieties of lightweight corals are also available. These are more porous and do not have the intense red color of the good quality corals. The advantage is that they are cheaper and available in abundance. Jewellery is crafted from these lightweight corals also. A long neck can carry off any design whereas a petite woman should try necklaces that are of collar-length or longer.

    Designers have let their imagination run riot and corals have given a dash of color to their designs. Whether the corals are set in plain gold or handcrafted silver, they are impossible to resist. Natural Red corals are collector’s items. Many people will pay a small fortune to own them. Corals are opaque and this is makes it difficult to differentiate the genuine from the false. Sometimes, colored wax is filled into the corals to give them a more dense red color, thus commanding a higher price.

    Before being polished, corals are dull and look like marine trees. They are then sorted, cleaned, cut and polished. The widest part of the coral tree is used to cut the stones. The stones are then polished and used for Jewellery. Earrings of Coral are the final purchase to complete your coral ensemble. Hanging or studs, with one stone or several small stones, coral earrings will frame the beauty of your face.

    Fiery Red, this mysterious stone from the sea, has powers to heal and ward off negative influences of the planets on your life. Wear corals to protect you and your loved ones, looking attractive is an added benefit of Coral Jewellery.

    Coral jewelry care

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    Coral jewelry care

    by Binashaji

    The gem is fragile and more brittle than other gems. It measures only 3.5 on the Mohs scale and the splendor of the coral will diminish if not taken care of. Like Pearls, Turquoise, some corals can be porous –these gems will get damaged if immersed in water for too long.

    Coral NecklaceAn ancient magic stone from the ocean. The coral is taken from the Coral trees that are created in shallow warm or cold ocean waters by tiny living creatures called Polyps. Millions of years are taken to create the coral reefs, which yield these gorgeous gems. Being organic in nature, corals are delicate and break more easily than other gemstones. These gems are found in a several colors – Gold, Black, Blue, White and in an assortment of shades of Red, from pinkish to deep blood red. The Black, Blue, White and Gold corals are rare but the red corals are available in abundance, although the superior quality deep red corals that are highly valued by connoisseurs are rare and command a high price. The best of these red corals are found in Japan and Italy.

    If you are being offered Coral Jewellery at throwaway prices, the corals are most probably imitation or of a lower quality. High quality corals are expensive. Corals are opaque and are polished to a high gloss after they have been cut. Fake corals are aplenty and it is difficult to spot an imitation. It is advisable to always buy Coral Jewellery from a reputed store. Corals are believed to have the power to ward of negative influences and endow the wearer with energy and vitality.

    Coral JewelleryCoral Jewellery does not need high maintenance. The gem is fragile and more brittle than other gems. It measures only 3.5 on the Mohs scale and the splendor of the coral will diminish if not taken care of. Like Pearls, Turquoise, some corals can be porous -these gems will get damaged if immersed in water for too long. Take care not to use too much water while wearing coral bracelets or rings. The water may also dull the polish of the coral making it look lackluster and unattractive. If you plan to go swimming, remove your Jewellery before diving in. The chlorine present in the water can cause the corals to spoil.

    Store your corals separately. Buy separate pouches for the Corals, so they do not get scratched. Other stones, which measure more than 5 on the Mohs scale, can leave scratches on your pretty red Firestones, do not mix up your corals with other gems. Your corals are precious and are becoming rare. Many countries have passed laws prohibiting corals from being taken out from the reefs, since the coral reefs are important in balancing the ocean’s ecology. Pollution, mining, indiscriminate harvesting of corals have destroyed many coral reefs, which have taken millions of years to form. Anyone who has been diving near a coral reef will agree that these reefs house a wealth of marine life and must be protected.

    Coral NecklaceRegularly check the stones in your Jewellery. If any of the stones are loose, visit your jeweler and have him fix it before you loose one expensive coral from your ring. Beads in a Bracelet or Necklace should be re-strung professionally, if they break. Place your coral beads flat inside a soft, velvet pouch. Clasps are important – tug gently at your Necklaces /Bracelets after wearing it so you are sure the clasp is firmly in place. Loose clasps can result in lost Jewellery.

    Harsh cosmetic products can also harm your corals. Use perfumes, sprays before wearing your Jewellery, sometimes the chemicals present in sprays can damage the corals. Do not use good old soap and water or any other detergents to clean corals. If you plan to buy a professional cleaner, check if it is coral friendly. The best way to clean coral is to just wipe it with a soft damp cloth after you have worn it. If your corals do get scratched despite care, take it to the jeweler for a polish; it will look as good as new.

    Authentic Coral Jewellery with good quality stones is a pleasure to own. These beautiful gems from the ocean look eye-catching and just a little care will go a long way with corals.

    Coral jewelry buying guide

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    Coral jewelry buying guide

    by Preeti Sharma

    The coral that is suitable for jewelry is not generally formed in reefs. It is found in small branch-like structures. It can be seen as the skeletal remains of the marine animals or the polyp corallicum. The most worthful coral is the noble red, also called corallicum rubrum. A typical and unique feature of precious corals is that they have a wonderful polish.

    Coral jewelry is exciting to wear. With distinct look and features from Gold, Platinum or Silver jewelry, coral jewelry has become popular quite fast. But don’t get carried away with the luster. Pause…hold back. Before you enter the market to buy your choice of coral jewelry designs, we have some important tips from the coral jewelry buying guide.

    All That You Need To Know Before You Buy Coral Jewelry

    Coral Jewelry-What is Coral?

    girl with coral necklaceCoral seems to be an excellent choice for jewelry. But, have you ever thought that where from coral comes actually? Coral is a sea product that grows in branches, which look much like dwarf underwater trees. In the whole cycle of making of coral, a marine gelatinous animal collects calcium carbonate around its body. It is a polyp made of calcite fibrous crystals.

    The polyps then create a branch like shape, built in the shape of hollow tubes fitted in one another. This makes for a sort of axial skeleton upon which the boneless coral polyps grow. They thrive a colony of their own and create the coral. A fully-grown coral remains covered with lime, barnacles, and salt.

    How To Select The Real Coral?

    The coral that is suitable for jewelry is not generally formed in reefs. It is found in small branch-like structures. It can be seen as the skeletal remains of the marine animals or the polyp corallicum. The most worthful coral is the noble red, also called corallicum rubrum. A typical and unique feature of precious corals is that they have a wonderful polish.

    The appearance of Calcareou Coral can range from semi translucent to opaque. Its color can go from light to dark pink and then to dark red. It is also found in white, orange and cream colors and also in purple and blue at times. The appearance of other variety of coral, Conchiolin Coral, can range from semi translucent to opaque. It is found in gray, black, yellow and dark brown colors.

    The Calcareous coral has hardness of -3 1/2 to 4 and fair toughness. While the Conchiolin coral has hardness of 3 and good toughness. Both the varieties of coral have glass like waxy to vitreous polish luster.

    There are many common enhancements that are done on coral that spoil their natural qualities. Dyeing the calcareous coral deepens and at times changes the color and saturation with epoxy. The dying will then hide cracks at the surface and make it fill with cavities in the low quality of Coral. It is a quite common practice that cheats the coral customers.

    Stay Away From Coral Simulants

    Coral JewelryYou also have to be careful in picking the right coral. Must buyers of coral end up in getting some other materials that are used to imitate the natural coral. There are all the chances for you to be mistaken with Plastic, man made Coral, Howlite, Shell, Ivory, Onyx/Calcite and Fossil Ivory as Coral. For Conchiolin Coral, the materials like plastic, Chalcedony and Jet are used for imitation.

    The physical look of the carbonate type of Coral is that it flaunts a distinct pattern of parallel stripes with a little different colour and transparence. The Glass simulants of the coral lacks the ideal structure of coral. They have a glassy luster and tend to have bubbles. The glass simulants can also display conchoidal fracture. The plastics simulants of Coral also do not have coral the structure and can possibly show molding lines. You can detect the shell simulants by their layered structure. It displays fine rippled lines on its surface.

    How To Test The Real Coral

    There are some facts and qualities about the real coral that you should keep in mind. The best coral should have a deep natural color. It is found in a standard (round or oval shape) and finished surface. The perfect coral does not have any dents or holes or perforations. It is smooth to touch.

    You can do some tests to identify the real coral. Place the real coral in a glass of cow’s milk. If the color of milk will change to the one with red tinge, the coral is real. The imitation coral cannot change the milk’s whiteness. Another interesting test you can carry out is by actually wearing it. A true coral changes its color as per the physical health of the wearer. It will resume its original color when the physical health of the person is restored. But, it will fade out prior to the disorder in the wearer’s physical health is evident.

    The Famous Market Places Of Coral

    It is difficult to find all the ideal conditions for the making of coral, such as right depth, intensity and temperature at one place. This is the reason there are less places in the world that provide best quality of coral. The best quality coral can be found in the southern Ireland, Madeira, Bay of Biscay, Canaries, Mauritius, Cape de Verde Islands, Japan, Hawaii, Australia, Mediterranean, Red Sea, Malay Archipelago and in the Japanese waters. Italy is the place that is considered the center of coral jewelry making. In Italy, Torre del Greco, near Naples is the place where the best quality of coral jewelry is made. You can buy a lot of jewelry designs of Coral, such as beautiful earrings, pendants, brooches, rings, tie bars, cuff links, belt buckles, pillboxes and inlaid jewelry boxes.

    The Colors Of Coral

    You can buy Coral in a great variety of colours that range from Dark Red, Pink, White, Spotted Pink, Orange, Blue, Violet, Black and Golden Brown. Each coral color has its own unique quality. Black coral is exotic and dramatic to look and rare to find. It is considered as a guard against misfortune for a long time now. When polished, the black coral shines with beautiful luster.

    Pink Coral is delicate found in utmost quantity in the entire length of Hawaiian chain. It is very dense and solid. The shaded colors in the large pink corals are the gem’s natural qualities. The value of pink coral depends on its rarity. The precious Red Coral is revered high since the early civilizations for its beautiful color, texture and luster. It is found in ocean depths of about 500 to 1,000 feet. Its rate of growth is very slow, only about 1/4 inch each year. This makes the red coral really highly treasured and prized.

    Blue Coral is thought to be in the initial stage of disintegration. This color generally expands only below the surface. It is an unusual variety found off in Cameroon. Hawaiian Gold Coral is rare by far. Its color tone ranges from sandy beige color to complete black. On the off side of Maui in Hawaii, this exquisite variety of coral is found with resin or lacquered texture. The only company in the world that creates jewelry from Hawaiian Gold Coral is Maui Divers.

    The Law That Concerns Your Purchase Of Coral Jewelry

    Only the corals that grow slow and live long are selected for jewelry and other ornamental purposes. The intensive collection of reefs threatens them. If you wish to buy the coral jewelry from overseas, it is important to make sure that you find out if you should take a CITES permit. When you are buying it at home, always enquire from the retailer whether the coral is imported with required CITES permit.

    As a buyer, you should first obtain the scientific (Latin) name present in the Control List of the coral. Check whether CITES regulates it or not. CITES regulates all hard corals. If it is a CITES species, the buyer requires a CITES export permit that the exporting country issues. Make sure that the coral producer obtains the CITES permit for you before your order your coral jewelry.

    To conclude, be very alert when you go off to buy the coral jewelry you like. Remember the guiding tips above to get the best deal. Happy Shopping!

    How coral is formed

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    How coral is formed

    by Preeti Sharma

    Actually, Coral is a substance formed by the skeletons of the sea animals. It may look like a multi color rock, but it is not. Coral is a living animal and belongs to the large group of animals that comprises of, jelly fish, sea anemones and hydroids.

    Coral is a colorful rock found underwater that is used for jewelry extensively. With their bright color range and nice quality, coral jewelry is appreciated throughout the world. You may admire the coral jewelry or may be proud of owing one, but have you ever thought how coral is formed. Not yet? So read on here to know the unique way how coral is formed.

    coral reefs
    image courtesy: National Geographic

    What is Coral?

    Actually, Coral is a substance formed by the skeletons of the sea animals. It may look like a multi color rock, but it is not. Coral is a living animal and belongs to the large group of animals that comprises of, jelly fish, sea anemones and hydroids. Corals ooze out a tough skeleton of limestone or calcium carbonate as protection for the coral Polyps.

    Live coral animals make a colony of individual Polyps. Each polyp makes a strong and hard skeleton that as a shape like a cup. It is known as calyx that is made for security and support. The skeleton is connected to the polyps around it. Therefore, the skeletons of hundreds coral polyps dwell together forming one coral colony.

    Corals are the sea animals that belong to the group of the Phylum Cnidaria with tentacles and stinging cells, also called nematocysts. They have a single opening in their body for the passing of food and waste. The living and healthy coral is colored brightly often.

    There are diverse coral formations that look like large domes, branching trees, small irregular crusts, or tiny organ pipes. The living coral forming animals color the formations in beautiful hues of tan, orange, yellow, and green. The coral animals cannot live in cold water below 65 ° F. This is the reason why coral reefs are found in shallow and tropical seas, mostly.

    Polyps

    The polyps are little carnivorous or meat eating animals that live in millions of number together. The polyps live together in large groups that are called colonies. The polyp is actually related to anemone. It consists of stomach and has a mouth at one end. The mouth is encircled by a good number of tentacles that are similar to feet. The polyp word is related to this fact actually, as in Greek the ‘Polyp’ word meaning ‘many feet’.

    The tentacles of polyps are well covered with small stinging cells. So when a small animal gets close and brushed against the tentacles, it gets killed. The prey then goes off to the stomach and is digested. Polyps are immovable from their homes made of limestone. They come out at night to feed most of the time.

    So, how do polyps form coral?

    The colony of coral grows by the budding of a single coral polyp that splits in two. It makes a matching copy of itself. Most of the polyps that make coral live together in colonies. The polyps attach themselves together with each other. There is a flat sheet of tissue that joins one polyp to the middle of the body of another polyp. The half of coral polyp stretches out above, while the remaining half is down under the connecting sheet.

    Continuously the polyps keep on creating the new skeletons at their bottom and sides. While doing this, they keep on going upwards and outwards from coral colony center. The coral polyps take away calcium present in the sea water and make their own limestone skeletons. In this way, they deposit limestone or calcium carbonate in the half region of their lower body halves.

    As the polyps die, they go away as limestone skeletons. These skeletons in future become the base of various barriers and ridges that are known as Coral Reefs. The living polyps live on the top of the old and dead skeletons that they have made. In this way the whole colony continues to grow, with the new polyps getting created and the old ones dying off. As there are new polyps growing, the group makes the limestone structure large and larger.

    The major part of the structure of single coral colony is actually made up of the dead skeletal material. A living and healthy coral has just a thin layer of living material that inhabits its surface.

    How do polyps reproduce?

    A coral polyp actually reproduces in using either of the two following ways:

    * One way can be to divide its own body to make two polyps

    * The other way is to produce sperm and eggs

    The eggs and sperm come out from coral polyps at the time just after the full moon in the month of November. They keep floating for about a few days. There are a small number of eggs that get fertilized, originate into larvae and then get settled on the reef. Once they get settled, they start together to begin new colonies. The colonies formed by polyps grow fast. You may be amazed to not e the fact that in three years one polyp can make a colony of 25,000 polyps!

    Coral reefs

    A strip of curdled coral at or close to the surface of ocean is known as coral reef. The coral reefs are made mostly of coral colonies. They are formed by the animals or plants that grow within them, largely the stony corals. Reefs have a history and life span of about more than about 450 million years on earth. The big coral groups have round or branching masses. Over thousands of years the accumulation of skeletal material forms a coral reef.Coral reefs generally grow in low tropical water. They have algae that need light and they grow sound only near the surface of clear water. Also echinoderms, molluscs, protozoa, sea cucumbers and sponges add to the budding reef. The mats of blue and green bacteria work to ambush and alleviate the structure. Some reefs also have sea grasses and mangroves growing on top of them. As the corals break surface of water they make the coral islands.

    Coral reefs are of four types, mainly:

    The fringing reefs around islands
    The barrier reefs near the landmass, for example the Great Barrier Reef of Australia
    The atolls that are actually hollow rings, formed on underwater volcanoes, like the islands of Bermuda
    The patch reefs are tiny circular and uneven reefs that rise from the floor of the lagoon or inside the atoll.

    Now that you know about how coral is formed, are you a bit more interested in coral jewelry?

    Coral in History

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    Coral in History

    by Preeti Sharma

    The Tabulate corals, arranged in tabular form, occurred in lime stones and calcareous sedimentary rock of the Ordovician (from 500 million to 425 million years ago) and Silurian (From 425 million to 405 million years ago) periods. They often formed low cushions or branch masses along the side of Rugose corals.

    Interested in jewelry made of coral? Then we are sure you will be also interested to know coral in history. How coral was developed in the past? How coral was used in the earlier days in jewelry and lot more. Come on and join this exciting exploration of coral in history.

    Geological History of Coral

    CoralCorals are first thought to be appeared in the Cambrian period. It was about 570 million years ago. Till the Ordovician period (from 500 million to 425 million years ago), corals were considered extremely rare fossils. Ah this time, Rugose and Tabulate corals were widely popular and became widespread.

    The Tabulate corals, arranged in tabular form, occurred in lime stones and calcareous sedimentary rock of the Ordovician (from 500 million to 425 million years ago) and Silurian (From 425 million to 405 million years ago) periods. They often formed low cushions or branch masses along the side of Rugose corals.

    In the middle of Silurian period, the number of these corals started to decline. Finally, they became no extant at the end of the Permian period (From 280 million to 230 million years ago). Gradually, the skeletons of Tabulate corals were compiled up in the form of calcium carbonate, called as Calcite.

    The Rugose corals were dominant in existence by the middle of the Silurian period. But slowly they also became extinct early in the Triassic period (from 230 million to 190 million years ago). The Rugose corals were found either in lone or in colonial settings. They were similar to the Tabulate corals and their skeletons were also composed of calcite. Most of the all right details of the skeletal structures are well preserved often. These fossils can be cut and polished for further use.

    Scleractinian corals can be diversified during the Mesozoic (from 230 million to 63 million years ago) and Cenozoic eras (approximately the last 63 million years). They are at the height of development these days. The fossils can be found in small number in rocks from Triassic period. Relatively, they were common fossils in rock from Jurassic and Cretaceous periods as well as Caenozoic era. Scleractinian corals’ skeletons that are composed of a figure of calcium carbonate known as Aragonite. Scleractinian coral are quite younger geologically as compared to the Tabulate and Rugose corals. The Scleractinian corals, aragonite skeleton are not preserved well and are often easy to get fossils of more old Tabulate and Rugose corals.

    It is found in studies that in the geological past, the corals were found abundantly, just like modern-day corals are found in the clear, warm and tropical waters of some particular part of the world today. The modern corals have fossil ancestors that make reefs deep under the ancient seas. There are some coral reefs that lie in the form of great structures amidst sedimentary rocks.

    The ancient reefs are not made completely of corals. The algae and sponges and fossilized remains of echinoids, brachiopods, bivalves, gastropods, and trilobites that were on the reefs contributed to make them. The fossil coral reefs are the prime locations to see the different types of fossils, besides corals.

    Corals are not limited to reefs only. There are several lonely corals that can be found in rocks where reefs are not present. The geologists have actually been able to date the age of the rocks in which they are found. It is particularly in the case of corals found in limestone of Carboniferous period.

    Coral Jewelry in Different Countries Through The Years

    The coral beads and artifacts are discovered in the graves of pre dynastic Egypt, dating back to as far as 4000 B.C. They are also found in the graves from Iron Age and Neolithic sepulchers from 10,000 B.C. All through the world, the museums have the collections of amulets and ornaments made of coral belonging to the period of 1000 B.C.

    The most ancient and traditional center to fashion coral is Torre del Greco, located near Naples. It was made by the King of Naples in 1870 and Robert Phillips, the jeweler of Cockspur Street London, got a decoration for services for the trade of coral. This can tell best about the popularity of coral jewelry in Victorian England times.

    Napoleon had a sundry taste for all Italian things, which acclaimed fashion for carved coral jewelry. The rose pink type of coral was the most sought after fashioned with flowers, especially with roses, cherubs, grotesque masks, chrysanthemums, leaves and fruit. In the early Victorian period, people wore the carved coral charms attached with formed clasps, tiny gold rings, decorated cuffs and other stylish jewelries.

    During the 1860’s, the coral beads and ovoid were arranged in gold brooches. In the 1870’s, people had coral in flowered gold brooches, in combination with diamonds and emeralds. It was unfortunate that gradually exposed so much with popularity and overuse, coral was declined in Victorian jewelry. Particularly in the so called proper circles, coral was considered to be vulgar. Towards the end of the 19th century, coral was rarely used in jewelry.

    The period of 1920’s and 1930’s observed resurgence and proved as an enhancement to the geometric forms prevalent in that period. But once again, it started to decline until the 1970’s.

    To talk about the use of coral in some particular countries-In India, coral had a high value and was often ornamented in the figures of gods. Same was the traditional use of coral in China, while the in Persia its color was mostly admired. The Tibetans consider the red coral to be symbolic of one of the avatars or incarnations of Buddha. The use of coral was highly prevalent in the 13th century that the famous traveler and historian Marco Polo also mentioned about it.
    In Africa, coral was worshipped in the ancient days. It was considered as the most invaluable gift that the ruler could bestow on people. Over a long period in past now, people all over the world have kept on taking delight in coral. The Renaissance and the Victorian periods assimilated it in the fine jewelry designs.

    What else we can tell about the importance of coral in history-American President Lincoln was highly fond of it; Europe witnessed shrewd rivalries for coral; since medieval to the present times, countries like Europe and Mediterranean have competed to be in charge of the coral fishing rights on the African coasts.

    After completing a long journey in history, coral is today available in the designs of earrings, rings, cameo brooches and necklaces and will continue to rule over the jewelry lover’s hearts.

    Aquamarine jewelry buying guide

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    Aquamarine jewelry buying guide

    by Theresa Smith

    Apart from reading as much about Aquamarine jewelry as you can, you should also take every opportunity to handle good jewelry. Knowing what to look for when buying Aquamarine jewelry will ensure that your money is well spent. Examine the work of well-known jewelry-craftsman and study the different designs.

    Aquamarine Jewelry – Few facts

    Aquamarine – the very name of this popular gemstone evokes mental images of the ocean’s splendor and vitality. This gem – composed of the mineral beryllium aluminum silicate – is pale greenish blue in color. It is said to have mystical powers and healing properties hence it being regarded as the universal symbol of youth, hope and health. While stones come in a range of colors the ideal color of Aquamarine is a refreshing pastel sea blue.

    Color:

    aquamarine jewelryStones with a clear blue color – without green or gray – are generally the most valuable. Though almost all gemstones contain some degree of blemishes, the highest quality Aquamarine is transparent, with no internal flaws or external imperfections. Aquamarine is a hard durable stone (7.5 to 8), which makes it a good choice for jewelry that is worn frequently like rings; and is readily available in larger sizes. It is especially dramatic when cut in a rectangular or oval shape, with facets, many angled sides or cut as a cabochon – a smooth dome without facets.

    Cut:

    A good cut displays an Aquamarine’s depth of color and liveliness while revealing the fewest imperfections. Aquamarine is found mainly in Brazil, Nigeria, Zambia, Madagascar and Ukraine. Focus on the details Apart from reading as much about Aquamarine jewelry as you can, you should also take every opportunity to handle good jewelry. Knowing what to look for when buying Aquamarine jewelry will ensure that your money is well spent. Examine the work of well-known jewelry-craftsman and study the different designs. Cultivate an expert eye by examining the piece from every perspective. Focus on the details such as the overall finish; check the quality of the stones and whether the stones have been set straight.

    Damages:

    Does the piece show signs that it has been damaged or repaired? Are the gemstones clean and free of scratches? Closely examine the color of the Aquamarine gemstones and the carat weight, which are key determining factors in assessing the value of the piece. Be especially critical when studying the design of the item. Ask questions like whether the style can be attributed to the period in which it was made, is the design balanced and proportioned, does it have eye appeal; and is it wearable? It may be beneficial to acquire some background knowledge from books to identify typical style trademarks, for example, Art Nouveau.

    It is also a good idea to wear the piece of jewelry before buying it to ensure it hangs right and is comfortable to wear. Bear in mind the ‘demand value’ of a jewelry piece if you are a collector. While identifying a piece that is highly sought or rare certainly affects its value, it is wise to be thoroughly acquainted with the market before investing in unusual jewelry pieces. Though the size of Aquamarine jewelry is dictated by fashion trends, collectors generally favor larger items. Albeit, buyer guidelines should at times be dismissed in favor of purchasing jewelry purely because the piece appeals to personal taste and passion.

    Aquamarine jewelry caring tips:

    To protect Aquamarine jewelry from damage and the risk of it losing color if left in direct sunlight, it is essential that the gemstone be cleaned at regular intervals and stored safely in a dark place when not worn. The clarity of the stone is maintained by immersing it in ultrasonic jewelry cleaner or lukewarm soapy water and cleaned with a soft bristle brush. Special care should be taken not to subject the jewelry to extreme temperature changes, or situation where it can get scratched or knocked. Storage in a jewelry case is recommended.

    Buyers guide for Aquamarine engagement rings

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    Buyers guide for Aquamarine engagement ring

    by Madhubanti_Rudra

    Aquamarine as a stone for engagement ring has become a rage among the young and stylish new generation couples who would choose a piece of jewellery which is comfortable to wear and at the same time speaks of individualistic style

    The grand celebration of tying the knot begins right with the engagement ceremony. The unwritten social contract between the families of the bride and groom that is the essence of engagement ceremony is surfaced through the exchange of rings between the couple. the aquamarine ring which is probably the most emotional piece of jewellery in one’s possession is a symbolic representation of eternity. Life long commitment towards one’s spouse finds its expression through this oldest ornament of the mankind.