"Canadian Gold Maple Leaf The Canadian Gold Maple Leaf (GML) is a gold bullion coin that is issued annually by the Government of Canada. It is produced by the Royal Canadian Mint. The Gold Maple Leaf is legal tender with a face value of 50 Canadian dollars. The market value of the metal varies, depending on the spot price of gold. Having a .9999 millesimal fineness (24 carats), in some cases .99999, the coin is among the purest official bullion coins worldwide. The standard version has a weight of minimum 1 troy ounce (31.10 grammes). Other sizes and denominations include"
"Colored gold Pure gold is slightly reddish yellow in color, but colored gold in various other colors can be produced. Colored golds can be classified to three groups: Pure 100% (in practice, 99.9% or better) gold is 24 karat by definition, so all colored golds are less than this, with the common being 18K (75%), 14K (58.5%), 10K (41.6%), and 9K (37.5%). ""White gold"" is an alloy of gold and at least one white metal (usually nickel, manganese, or palladium). Like yellow gold, the purity of white gold is given in karats. White gold's properties vary depending on the metals"
"common millesimal finenesses used for precious metals and the most common terms associated with them. The karat or carat (variant US spelling and standard UK spelling; US symbol K or kt, UK symbol C) is a fractional measure of purity for gold alloys, in parts fine per 24 parts whole. The karat system is a standard adopted by US federal law. 24-karat gold is pure (while 100% purity is unattainable, this designation is permitted in commerce for 99.95% purity), 18-karat gold is 18 parts gold, 6 parts another metal (forming an alloy with 75% gold), 12-karat gold is 12 parts"
"sapphire blue colored gold of 20–23K can also be obtained by alloying with ruthenium, rhodium and three other elements and heat-treating at 1800 °C, to form the 3–6 micrometers thick colored surface oxide layer. Colored gold Pure gold is slightly reddish yellow in color, but colored gold in various other colors can be produced. Colored golds can be classified to three groups: Pure 100% (in practice, 99.9% or better) gold is 24 karat by definition, so all colored golds are less than this, with the common being 18K (75%), 14K (58.5%), 10K (41.6%), and 9K (37.5%). ""White gold"" is an"
"Gold Gold is a chemical element with symbol Au (from ) and atomic number 79, making it one of the higher atomic number elements that occur naturally. In its purest form, it is a bright, slightly reddish yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal and a group 11 element. It is one of the least reactive chemical elements and is solid under standard conditions. Gold often occurs in free elemental (native) form, as nuggets or grains, in rocks, in veins, and in alluvial deposits. It occurs in a solid solution series with the native"
"and 25% of alloy(s). The quantity of gold ""by volume"" in a less-than-24-karat gold alloy differs according to the alloy(s) used. For example, knowing that standard 18-karat yellow gold consists of 75% gold, 12.5% silver and the remaining 12.5% of copper (all by mass), the volume of pure gold in this alloy will be 60% since gold is much denser than the other metals used: 19.32 g/cm for gold, 10.49 g/cm for silver and 8.96 g/cm for copper. This formula gives the amount of gold in cubic centimeters or in milliliters in an alloy: where To have the percentage of"
"copper, by mass. Sterling silver contains 92.5% silver and 7.5%, by mass, of other metals, usually copper. Various ways of expressing fineness have been used and two remain in common use: ""millesimal fineness"" expressed in units of parts per 1,000 and ""karats"" used only for gold. Karats measure the parts per 24, so that 18 karat = = 75% and 24 karat gold is considered 100% gold. Millesimal fineness is a system of denoting the purity of platinum, gold and silver alloys by parts per thousand of pure metal by mass in the alloy. For example, an alloy containing 75%"
"Carat (mass) The carat (ct) (not to be confused with the karat, sometimes spelled carat, a unit of purity of gold alloys), is a unit of mass equal to 200 mg (0.2 g; 0.007055 oz) and is used for measuring gemstones and pearls. The current definition, sometimes known as the metric carat, was adopted in 1907 at the Fourth General Conference on Weights and Measures, and soon afterwards in many countries around the world. The carat is divisible into one hundred ""points"" of two milligrams each. Other subdivisions, and slightly different mass values, have been used in the past in"
"the volume of gold in an alloy, divide the volume of gold in cubic centimetres or in millilitres by the total volume of the alloy in cubic centimetres or in millilitres. For 10-carat gold, the gold volume in the alloy represents about 26% of the total volume for standard yellow gold. Talking about purity according to mass could lead to some misunderstandings; for many people, purity means volume. ""Karat"" is a variant of ""carat"". First attested in English in the mid-15th century, the word ""carat"" came from Middle French , in turn derived either from Italian or Medieval Latin ."
"gold (12 parts another metal), and so forth. In England, the karat was divisible into four grains, and the grain was divisible into four quarts. For example, a gold alloy of fineness (that is, 99.2% purity) could have been described as being ""23-karat, 3-grain, 1-quart gold"". The karat fractional system is increasingly being complemented or superseded by the millesimal system, described above. Conversion between percentage of pure gold and karats: However, this system of calculation gives only the mass of pure gold contained in an alloy. The term ""18-karat gold"" means that the alloy's mass consists of 75% of gold"
"same atomic number, or number of protons. Nuclear scientists, however, define a pure element as one that consists of only one stable isotope. For example, a copper wire is 99.99% chemically pure if 99.99% of its atoms are copper, with 29 protons each. However it is not isotopically pure since ordinary copper consists of two stable isotopes, 69% Cu and 31% Cu, with different numbers of neutrons. However, a pure gold ingot would be both chemically and isotopically pure, since ordinary gold consists only of one isotope, Au. Atoms of chemically pure elements may bond to each other chemically in"
"gold is denoted as ""750"". Many European countries use decimal hallmark stamps (i.e., ""585"", ""750"", etc.) rather than ""14K"", ""18K"", etc., which is used in the United Kingdom and United States. It is an extension of the older karat system of denoting the purity of gold by fractions of 24, such as ""18 karat"" for an alloy with 75% (18 parts per 24) pure gold by mass. The millesimal fineness is usually rounded to a three figure number, particularly where used as a hallmark, and the fineness may vary slightly from the traditional versions of purity. Here are the most"
"per troy ounce in late 2014 and 2015. Because of the softness of pure (24k) gold, it is usually alloyed with base metals for use in jewelry, altering its hardness and ductility, melting point, color and other properties. Alloys with lower karat rating, typically 22k, 18k, 14k or 10k, contain higher percentages of copper or other base metals or silver or palladium in the alloy. Nickel is toxic, and its release from nickel white gold is controlled by legislation in Europe. Palladium-gold alloys are more expensive than those using nickel. High-karat white gold alloys are more resistant to corrosion than"
"or ingots, it is generally accepted worldwide that anything above .999 fine qualifies as 24K. Below is a karat weight to fineness conversion chart. Correlation between karats and fineness The fineness is often converted to a percent, as well. If a gold coin has a fineness of .900, that is 90.0% pure gold. If a gold coin has a fineness of .850, then the gold coin is 85.0% pure. Coins have varied greatly in fineness through history. Notable historical standards that were closely adhered-to include the crown gold (22 karat) used in all English gold coins intended for circulation from"
"(58 to 75%) is not recommended. Gold is about as soft as lead and is easily scratched. These scratches can irritate the body, especially in new piercings. Tongue jewelry made from gold is not recommended as chewing on the beads is common. To avoid the irritation of damaged jewelry from such scratches and flaws, gold colored titanium jewelry is a safer substitute. Piercing jewelry is often made of a gold alloy, the most common being 18k, with 24k being entirely pure and much softer. 18k gold usually contains 75% gold and the remaining 25% copper, silver and traces of other"
"example, a gold ingot identified as being .999 fine will be 999/1000 pure gold, with the other 1/1000 being impurities. Karat weight (K or kt) is a traditional fraction-based system used to denote the fineness of gold, with one karat being equal to 1/24 part of pure gold in an alloy. With the precision of modern assaying techniques, however, the fineness of gold ingots and bullion is more likely to appear as a decimal measurement. In this system, pure gold would be denoted as 1.000 fine. However, since absolutely pure gold is very soft and therefore not suitable for coinage"
"mass). Gold nuggets in Australia often are 23K or slightly higher, while Alaskan nuggets are usually at the lower end of the spectrum. Purity can be roughly assessed by the nugget color, the richer and deeper the orange-yellow the higher the gold content. Nuggets are also referred to by their fineness, for example ""865 fine"" means the nugget is 865 parts per thousand in gold by mass. The common impurities are silver and copper. Nuggets high in silver content constitute the alloy electrum. In literature, there are two nuggets that claim their status as the biggest gold nuggets in the"
"Gold leaf Gold leaf is gold that has been hammered into thin sheets by goldbeating and is often used for gilding. Gold leaf is available in a wide variety of karats and shades. The most commonly used gold is 22-karat yellow gold. Gold leaf is a type of metal leaf, but the term is rarely used when referring to gold leaf. The term ""metal leaf"" is normally used for thin sheets of metal of any color that do not contain any real gold. Pure gold is 24 karats. Real, yellow gold leaf is approximately 91.7% pure gold. Silver-colored white gold"
"2006, the United States Mint began producing the American Buffalo gold bullion coin with a purity of 99.99%. The Australian Gold Kangaroos were first coined in 1986 as the Australian Gold Nugget but changed the reverse design in 1989. Other modern coins include the Austrian Vienna Philharmonic bullion coin and the Chinese Gold Panda. , gold is valued at around $42 per gram ($1,300 per troy ounce). Like other precious metals, gold is measured by troy weight and by grams. The proportion of gold in the alloy is measured by ""karat"" (k), with 24 karat (24k) being pure gold, and"
"gold elements with skin should be avoided as exposure to sweat may result in metal leaching and discoloration of the metal surface. Purple gold (also called amethyst gold and violet gold) is an alloy of gold and aluminium rich in gold-aluminium intermetallic (AuAl). Gold content in AuAl is around 79% and can therefore be referred to as 18 karat gold. Purple gold is more brittle than other gold alloys (a serious fault when it forms in electronics), as it is an intermetallic compound instead of a malleable alloy, and a sharp blow may cause it to shatter. It is therefore"
"electrodes, platinum-resistance thermometers, dentistry equipment, and jewelry. Because only a few hundred tonnes are produced annually, it is a scarce material, and is highly valuable and is a major precious metal commodity. Being a heavy metal, it leads to health issues upon exposure to its salts, but due to its corrosion resistance, it is not as toxic as some metals. Its compounds, most notably cisplatin, are applied in chemotherapy against certain types of cancer. Gold is a dense, soft, shiny, malleable and ductile metal. It is a chemical element with the symbol Au and atomic number 79. Pure gold has"
"different locations. In terms of diamonds, a paragon is a flawless stone of at least 100 carats (20 g). The ANSI X.12 EDI standard abbreviation for the carat is CD. First attested in English in the mid-15th century, the word ""carat"" comes from Italian ""carato"", which comes from Arabic ""qīrāṭ"" قيراط, in turn borrowed from Greek ""kerátion"" κεράτιον 'carob seed', a diminutive of ""keras"" 'horn'. It was a unit of weight, though unlikely to have been used to measure gold in classical times. Carob seeds have been used throughout history to measure jewelry, because it was believed that there was"
"antimony, and bismuth. Native chromium has been found in small grains in Sichuan, China and other locations. Native metal A native metal is any metal that is found pure in its metallic form in nature. Metals that can be found as native deposits singly or in alloys include aluminium, antimony, arsenic, bismuth, cadmium, chromium, cobalt, indium, iron, manganese, molybdenum, nickel, rhenium, selenium, tantalum, tellurium, tin, titanium, tungsten, vanadium, and zinc, as well as two groups of metals: the gold group, and the platinum group. The gold group consists of gold, copper, lead, aluminium, mercury, and silver. The platinum group consists"
"copper content. Examples of the common alloys for 18K rose gold, 18K red gold, 18K pink gold, and 12K red gold: Up to 15% zinc can be added to copper-rich alloys to change their color to reddish yellow or dark yellow. 14K red gold, often found in the Middle East, contains 41.67% copper. The highest karat version of rose gold, also known as crown gold, is 22 karat. During ancient times, due to impurities in the smelting process, gold frequently turned a reddish color. This is why many Greco-Roman texts, and even many texts from the Middle Ages, describe gold"
"purple gold can be made by alloying with aluminium. Less commonly, addition of manganese, aluminium, indium and other elements can produce more unusual colors of gold for various applications. Colloidal gold, used by electron-microscopists, is red if the particles are small; larger particles of colloidal gold are blue. Gold has only one stable isotope, , which is also its only naturally occurring isotope, so gold is both a mononuclidic and monoisotopic element. Thirty-six radioisotopes have been synthesized, ranging in atomic mass from 169 to 205. The most stable of these is with a half-life of 186.1 days. The least stable"
"mint gold bars are nearly pure gold. Bars made from melted gold coins, called ""coin bars"", are the same composition as the original coins, which is 90% gold. Unlike many .999 fine gold bullion coins minted in modern times for holding today, the coin alloy for pre-1933 US coins, which were intended for circulation, was a tougher and wear-resistant .900 fine alloy (balance copper) used for all US gold coins since 1837. (See crown gold for further gold coin alloy history.) The U.S. holds more gold than any other country, with about 8,133 metric tons in total (not just at"
"purity of sample. Karatmeter The Karatmeter is a scientific device bought and named by India-based Titan Company Limited (TATA Group) which uses X-rays to give an exact reading of the purity of gold. Due to its very high precision and fast result, X-ray analysis has been adopted by international agencies in India as part of the certification process used to hallmark gold. It is an accurate, non-destructive means of testing the purity of gold and other related elements. X-Ray method of Gold analysis gives the purity of gold upto 10-12 microns and hence it gives the analysis of coating only."
"g or possibly up to 5 g less. Therefore, the metric equivalent of 1 ""siliqua"" was approximately 189 mg. The Greeks had a similar unit of the same value. Gold fineness in carats comes from carats and grains of gold in a solidus of coin. The conversion rates 1 solidus = 24 carats, 1 carat = 4 grains still stand. Woolhouse's ""Measures, Weights and Moneys of all Nations"" gives gold fineness in carats of 4 grains, and silver in pounds of 12 troy ounces of 20 pennyweight each. Carat (mass) The carat (ct) (not to be confused with the karat,"
"the bar. A refiner doing $1 billion of business each year that marked .980 pure bars as .999 fine would make about an extra $20 million in profit. In the United States, the actual purity of gold articles must be no less than .003 less than the marked purity (e.g. .996 fine for gold marked .999 fine), and the actual purity of silver articles must be no less than .004 less than the marked purity. A piece of alloy metal containing a precious metal may also have the weight of its precious component referred to as its fine weight. For"
"Crown gold Crown gold is a 22 karat (kt) gold alloy used in the crown coin introduced in England in 1526 (by Henry VIII) to replace the earlier gold sovereign coins which were made from the softer 23 kt gold and which thereby had invited both deliberate filing and also non-intentional wear. The 22 kt standard has been used for British gold coins ever since this change which is 91.667% gold (or 22 parts out of 24). The alloying metal in England was and is traditionally copper-only, although a component of 1.25% silver replacing the same weight of copper, as"
"lower karat numbers proportionally less. The purity of a gold bar or coin can also be expressed as a decimal figure ranging from 0 to 1, known as the millesimal fineness, such as 0.995 being nearly pure. The price of gold is determined through trading in the gold and derivatives markets, but a procedure known as the Gold Fixing in London, originating in September 1919, provides a daily benchmark price to the industry. The afternoon fixing was introduced in 1968 to provide a price when US markets are open. Historically gold coinage was widely used as currency; when paper money"
"the most expensive price per carat. They will typically run in the hundreds of thousands of dollars per carat range. Since they are the rarest color, it is difficult to find them in large sizes, and they are mostly found in sizes less than 1 carat. Red diamonds only exist with one color intensity, Fancy, although their clarities can range from Flawless to Included, just like white diamonds. The largest and most flawless red diamond is the 5.11 carat Fancy Red Moussaieff Red Diamond, which has internally flawless clarity. Despite decades of research, scientists are still inconclusive as to the"
"10–30 g/km). In general, gold concentrations for south Atlantic and central Pacific samples are the same (~50 femtomol/L) but less certain. Mediterranean deep waters contain slightly higher concentrations of gold (100–150 femtomol/L) attributed to wind-blown dust and/or rivers. At 10 parts per quadrillion the Earth's oceans would hold 15,000 tonnes of gold. These figures are three orders of magnitude less than reported in the literature prior to 1988, indicating contamination problems with the earlier data. A number of people have claimed to be able to economically recover gold from sea water, but they were either mistaken or acted in an"