Exclusive jewelry with valuable materials
Exclusive jewelry with valuable materials
Jewellery (jewelry in American English) is a personal ornament, such as a necklace, ring, or bracelet, made from jewels, precious metals or other substance.
The word jewellery is derived from the word jewel, which was anglicised from the Old French "jouel" in around the 13th century. Further tracing leads back to the Latin word "jocale", meaning plaything. Jewellery is one of the oldest forms of body adornment; recently found 100,000 year-old Nassarius shells that were made into beads are thought to be the oldest known jewellery.
Although in earlier times jewellery was created for more practical uses, such as wealth storage and pinning clothes together, in recent times it has been used almost exclusively for decoration. The first pieces of jewellery were made from natural materials, such as bone, animal teeth, shell, wood, and carved stone. Jewellery was often made for people of high importance to show their status and, in many cases, they were buried with it.
Jewellery is made out of almost every material known and has been made to adorn nearly every body part, from hairpins to toe rings and many more types of jewellery. While high-quality and artistic pieces are made with gemstones and precious metals, less-costly costume jewellery is made from less-valuable materials and is mass-produced.
Gemstones
A gemstone is a mineral, rock (such in the case of lapis lazuli), or petrified material that when cut or faceted and polished is collectible or can be used in jewelry. Others are organic (such as amber, which is fossilised tree resin, and jet, a form of coal). Some gemstones which may be generally considered precious or beautiful are too soft or too fragile to be used in jewelry (for example, single-crystal rhodochrosite) but are exhibited in museums and are sought by collectors.
Characteristics and classification
Gemstones are described by gemologists using technical specifications. First, what is it made of, or its chemical composition. Diamonds for example are made of carbon (C), rubies of aluminium oxide (Al2O3). Next, many gems are crystals which are classified by crystal system such as cubic or trigonal or monoclinic. 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.
Gems are classified into different groups, species, and varieties. For example, ruby is the red variety of the species corundum, while any other color of corundum is considered sapphire. Emerald (green), aquamarine (blue), bixbite (red), goshenite (colorless), heliodor (yellow), and morganite (pink) are all varieties of the mineral species beryl.
Gems have refractive index, dispersion, specific gravity, hardness, cleavage, fracture, and lustre. They may exhibit pleochroism or double refraction. They may have luminescence and a distinctive absorption spectrum.
Material or flaws within a stone may be present as inclusions. The gem may occur in certain locations, called the "occurrence."
A gemstone is prized especially for great beauty or perfection so appearance is almost always the most important attribute of gemstones. Characteristics that make a stone beautiful or desirable are colour, unusual optical phenomena within the stone, an interesting inclusion such as a fossil, rarity, and sometimes the form of the natural crystal. Diamond is prized highly as a gemstone since it is the hardest naturally occurring substance known and is able to reflect light with fire and sparkle when faceted. However, diamonds are far from rare with millions of carats mined each year.
Traditionally, common gemstones were classified into precious stones (cardinal gems) and semi-precious stones. The former category was largely determined by a history of ecclesiastical, devotional or ceremonial use and rarity. Only five types of gemstones were considered precious: diamond, ruby, sapphire, emerald, and amethyst. In current usage by gemologists, all gems are considered precious, although four of the five original "cardinal gems" (excluding the now-common amethyst) are usually—but not always—the most valuable.
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