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Earrings and other body rings are also considered to be jewellery, while body art is not. Also, items affixed to a garment, such as buttons, are not considered to be jewellery, even if they are unusual and highly decorative. If you are looking to buy jewellery online then our categoriesed listings will help you find great jewellery sites from around the web.Also, items such as belts and handbags etc. are not considered to be jewellery, and are considered to be accessories. Simply click a category on the left to view a list of related sites. Visiting a number of antique jewellery dealers is easier online, improving your chances of finding that perfect piece at a price that it "cheap as chips".
A diamond is a form of carbon
A diamond is a form of carbon that was created deep within the core of the earth more than 3 billion years ago and brought to the surface by volcanic eruption. In diamond, each carbon atom is bonded to four other carbon atoms in a tetrahedral structure, like a pyramid. Each link or bond is the same length, and the tetrahedral formation is therefore completely regular.Theoretically a perfect diamond crystal could be composed of one giant molecule of carbon. After the magma cooled, it solidified into kimberlite, where the precious rough diamond is still found today. It is the strength and regularity of this bonding which makes diamond very hard, non-volatile and resistant to chemical attack.
Gemstones are identified by gemologists
Gemstones are identified by gemologists. The first characteristic a gemologist uses to identify a gemstone is its chemical composition. Gems are characterized in terms of refractive index, dispersion, specific gravity, hardness, cleavage, fracture, and luster. They may exhibit pleochroism or double refraction. Who describe gems and their characteristics using technical terminology specific to the field of gemology.Next, many gems are crystals which are classified by their crystal system such as cubic or trigonal or monoclinic. They may have luminescence and a distinctive absorption spectrum. For example, diamonds are made of carbon (C) and rubies of aluminium oxide (Al2O3). Another term used is habit, the form the gem is usually found in. For example diamonds, which have a cubic crystal system, are often found as octahedrons.
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