Portal:Gemology and Jewelry
Gemology (or gemmology) is the science, art and profession of identifying and evaluating gemstones. It is considered a geoscience and a branch of mineralogy. Some jewelers are academically trained gemologists and are qualified to identify and evaluate gems. Recently, the demand for gemological services has grown, as increasing quantities of synthetic gems such as cubic zirconia and synthetic moissanite are manufactured. Gemologists perform such work as the identification of synthetic and natural gemstones, fracture-filled gemstones, and color-enhanced or treated natural gemstones.
A gemstone is a mineral, rock, or petrified material that when cut or faceted and polished is collectable or can be used in jewelry. Gemstones are basically categorized by their crystal structure, specific gravity, refractive index, other optical properties, and hardness.
Jewellery (or jewelry) 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.
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 jewelry is made from less-valuable materials and is mass-produced. Template:/box-footer
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Turquoise is an opaque, blue-to-green mineral that is a hydrous phosphate of copper and aluminum, with the chemical formula CuAl6(PO4)4(OH)8·4H2O. It is rare and valuable in finer grades and has been prized as a gem and ornamental stone for thousands of years owing to its unique hue. In recent times turquoise, like most other opaque gems, has been devalued by the introduction of treatments, imitations, and synthetics onto the market, some difficult to detect even by experts.
The substance has been known by many names, but the word turquoise was derived around 16th century from the French language either from the word for Turkish (Turquois) or dark-blue stone (pierre turquin). This may have arisen from a misconception: turquoise does not occur in Turkey but was traded at Turkish bazaars to Venetian merchants who brought it to Europe. The colour, however, has been employed extensively in the decorative tiles adorning Turkish places of worship and homes for hundreds of years, beginning with the Seljuks, and the association quite possibly has caused the name to take root.
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Credit: Camp4joy.org, User:Jabez
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