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  • Jewelry Material : Diamond

    In mineralogy, diamond (from the ancient Greek αδάμας – adámas “unbreakable”) is a metastable allotrope of carbon, where the carbon atoms are arranged in a variation of the face-centered cubic crystal structure called a diamond lattice. Diamond is less stable than graphite, but the conversion rate from diamond to graphite is negligible at standard conditions. Diamond is renowned as a material with superlative physical qualities, most of which originate from the strong covalent bonding between its atoms. In particular, diamond has the highest hardness and thermal conductivity of any bulk material. Those properties determine the major industrial application of diamond in cutting and polishing tools and the scientific applications indiamond knives and diamond anvil cells.
    Because of its extremely rigid lattice, it can be contaminated by very few types of impurities, such as boron and nitrogen. Small amounts of defects or impurities (about one per million of lattice atoms) color diamond blue (boron), yellow (nitrogen), brown (lattice defects), green (radiation exposure), purple, pink, orange or red. Diamond also has relatively high optical dispersion (ability to disperse light of different colors).
    Most natural diamonds are formed at high temperature and pressure at depths of 140 to 190 kilometers (87 to 120 mi) in the Earth’s mantle. Carbon-containing minerals provide the carbon source, and the growth occurs over periods from 1 billion to 3.3 billion years (25% to 75% of the age of the Earth). Diamonds are brought close to the Earth′s surface through deep volcanic eruptions by a magma, which cools into igneous rocks known askimberlites and lamproites. Diamonds can also be produced synthetically in a high-pressure high-temperature process which approximately simulates the conditions in the Earth’s mantle. An alternative, and completely different growth technique is chemical vapor deposition (CVD). Several non-diamond materials, which include cubic zirconia and silicon carbide and are often called diamond simulants, resemble diamond in appearance and many properties. Special gemological techniques have been developed to distinguish natural and synthetic diamonds and diamond simulants.



  • Jewelry Material : Gold

    Gold is a chemical element with the symbol Au and atomic number 79. It is a dense, soft, malleable, and ductile metal with an attractive, bright yellow color and luster that is maintained without tarnishing in air or water. Chemically, gold is a transition metal and a group 11 element. It is one of the least reactive chemical elements, solid under standard conditions. The metal therefore occurs often in free elemental (native) form, as nuggetsor grains in rocks, in veins and in alluvial deposits. Less commonly, it occurs in minerals as gold compounds, such as with tellurium as calaverite,sylvanite and krennerite.
    Gold resists attacks by individual acids, but it can be dissolved by aqua regia (nitro-hydrochloric acid), so named because it dissolves gold. Gold also dissolves in alkaline solutions of cyanide, which have been used in mining. It dissolves in mercury, forming amalgam alloys; is insoluble innitric acid, which dissolves silver and base metals, a property that has long been used to confirm the presence of gold in items, giving rise to the term acid test.

     



  • Earring

    An earring is a piece of jewellery attached to the ear via a piercing in the earlobe or another external part of the ear (except in the case of clip earrings, which clip onto the lobe). Earrings are worn by both sexes, although more common among women, and have been used by different civilizations in different times.
    Common locations for piercings, other than the earlobe, include the rook, tragus, and across the helix (see image at right).[citation needed] The simple term “ear piercing” usually refers to an earlobe piercing, whereas piercings in the upper part of the external ear are often referred to as “cartilagepiercings”. Cartilage piercings are more complex to perform than earlobe piercings and take longer to heal.
    Earring components may be made of any number of materials, including metal, plastic, glass, precious stone, beads, wood, bone, and other materials. Designs range from small loops and studs to large plates and dangling items. The size is ultimately limited by the physical capacity of the earlobe to hold the earring without tearing. However, heavy earrings worn over extended periods of time may lead to stretching of the earlobe and the piercing.

     



  • Bracelet

    A bracelet is an article of jewelry that is worn around the wrist. When it is worn around the ankle it is called an ankle bracelet or anklet. A boot bracelet is used to decorate boots. Bracelets can be manufactured from metal, leather, cloth, plastic or other materials and sometimes contain jewels, rocks, wood, shells, crystals, metal or plastic hoops, pearls and many more materials. Bracelets are also used for medical and identification purposes, such as allergy bracelets and hospital patient-identification tags and also bracelet tags worn for new born babies.



  • Necklace

    A necklace is an article of jewellery which is worn around the neck. Necklaces are frequently formed from a metal jewellery chain. Others are woven or manufactured from cloth using string or twine.
    Common features of necklaces include features such as colorful stones (particularly gemstones or jewels), wood (usually carved or polished), art glass, feathers, shells, beads or corals – a wide, wide variety of other adornments have also been used. If a necklace includes a primary hanging feature, it is called a pendant; if the pendant is itself a small container, that is called a locket.



  • Ring

    A ring is a circular band, usually in metal, worn as ornamental jewellery around the finger, or sometimes the toe; it is the most common current meaning of the word “ring”. Strictly speaking a normal ring is a finger ring (which may be hyphenated); other types of rings worn as ornaments are earrings, bracelets for the wrist, armlets or arm rings, toe rings and torcs or neck rings, but except perhaps for toe rings, the plain term “ring” is not normally used to refer to these.
    Rings are traditionally usually in metal but can be of almost any material: metal, plastic, stone, wood, bone, glass, gemstone to name a few. They may be set with a gem or stone of some sort, which is often a precious or semi-precious gemstone such as diamond, ruby,sapphire or emerald, but can also be of almost any material.