Helpful Information about Sections in Jewellery
The name diamond derives from the ancient Greek adamas ( "invincible). They have been treasured as gemstones since their use as religious icons in ancient India and usage in engraving tools also dates to early human history. Roughly 49% of diamonds originate from central and southern Africa, although significant sources of the mineral have been discovered in Canada, India, Russia, Brazil, and Australia. They are mined from kimberlite and lamproite volcanic pipes, which brought to the surface the diamond crystals from deep in the Earth where the high pressure and temperature enables the formation of the crystals. The mining and distribution of natural diamonds are subjects of frequent controversy such as with concerns over the sale of conflict diamonds by African paramilitary groups.
1. Diamond Colour- The less colour, the better (and more expensive) the diamond.* Diamond colour is graded on a scale of D to S, with D representing 'colourless' through to S, representing Very Light colour (yellow).
2. Diamond Clarity- The higher the clarity, the better (and more expensive) the diamond. Almost all diamonds have naturally occurring minute crystals, cleavages and small impurities called inclusions. Diamond clarity is graded on a scale range from Flawless (F) through VS to Inclusions (I).
3. Diamond Cut- There are several shapes of diamond available, the most popular being Brilliant Cut. Other cuts are baguette cut, emerald cut, marquise cut, pear, heart and the Princess cut.
4. Diamond Carat weight- A Carat is 200 milligrams in weight. Carat is a measure of weight- A carat is divided into 100 points, so that a 1/2 carat diamond can also be referred to as a 50 point diamond. As the carat weight increases, the price increases dramatically. For example, a 100 point diamond might cost three times as much as a 50 point diamond, all other factors (colour, clarity and cut) being equal.
Gold (IPA: /ˈgold/) is a chemical element with the symbol Au (from the Latin aurum) and atomic number 79. It is a highly sought-after precious metal which, for many centuries, has been used as money, a store of value and in jewellery. The metal occurs as nuggets or grains in rocks, underground "veins" and in alluvial deposits. It is one of the coinage metals. Gold is dense, soft, shiny and the most malleable and ductile of the known metals. Pure gold has an attractive bright yellow colour and is one of only two colored metal elements, the other being copper. All other metals are silver or gray. In medieval times, gold was often seen as beneficial for the health, in the belief that something that rare and beautiful could not be anything but healthy. Even some modern esotericists and forms of alternative medicine assign metallic gold a healing power. Some gold salts do have anti-inflammatory properties and are used as pharmaceuticals in the treatment of arthritis and other similar conditions. However, only salts and radioisotopes of gold are of pharmacological value, as elemental (metallic) gold is inert to all chemicals it encounters inside the body.
Pure gold is too soft for ordinary use and is typically hardened by alloying with copper or other base metals.
The gold content of gold alloys is measured in carats (k), pure gold being designated as 24k. Because of the softness of pure (24k) gold, it is usually alloyed with base metals for use in jewellery, altering its hardness and ductility, melting point, color and other properties. Alloys with lower "k", typically 22k, 18k, 14k or 10k, contain higher percentages of copper, silver or other base metals in the alloy. Copper is the most commonly used base metal, yielding a redder metal. Eighteen carat gold containing 25% copper is found in antique and Russian jewelry and has a distinct, though not dominant, copper cast, creating an attractively warm color (rose gold). Fourteen carat gold-copper alloy is nearly identical in color to certain bronze alloys, and both may be used to produce police and other badges. Blue gold can be made by alloying with iron and purple gold can be made by alloying with aluminum, although rarely done except in specialized jewelry. Fourteen and eighteen carat gold alloys with silver alone appear greenish-yellow and are referred to as green gold. White gold alloys can be made with palladium or nickel. White 18 carat gold containing 17.3% nickel, 5.5% zinc and 2.2% copper is silver in appearance. Nickel is toxic, however, and its release from nickel white gold is controlled by legislation in Europe. Alternative white gold alloys are available based on palladium, silver and other white metals (World Gold Council), but the palladium alloys are more expensive than those using nickel. High-carat white gold alloys are far more resistant to corrosion than are either pure silver or sterling silver.