Precious metal

A precious metal is a rare, naturally occurring metallic chemical element of high economic value. Chemically, the precious metals tend to be less reactive than most elements (see noble metal). They are usually ductile and have a high lustre. Historically, precious metals were important as currency but are now regarded mainly as investment and industrial commodities. Gold, silver, platinum, and palladium each have an ISO 4217 currency code.

The best known precious metals are the coinage metals, which are gold and silver. Although both have industrial uses, they are better known for their uses in art, jewelry, and coinage. Other precious metals include the platinum group metals: ruthenium, rhodium, palladium, osmium, iridium, and platinum, of which platinum is the most widely traded.[1] The demand for precious metals is driven not only by their practical use but also by their role as investments and a store of value. Historically, precious metals have commanded much higher prices than common industrial metals.

Assortment of noble metals

1,000 oz silver bar

A metal is deemed to be precious if it is rare. The discovery of new sources of ore or improvements in mining or refining processes may cause the value of a precious metal to diminish. The status of a "precious" metal can also be determined by high demand or market value. Precious metals in bulk form are known as bullion and are traded on commodity markets. Bullion metals may be cast into ingots or minted into coins. The defining attribute of bullion is that it is valued by its mass and purity rather than by a face value as money.

Purity and mass

Johnson Matthey 500 grammes silver bullion
500 g silver bullion bar produced by Johnson Matthey

The level of purity varies from issue to issue. "Three nines" (99.9%) purity is common. The purest mass-produced bullion coins are in the Canadian Gold Maple Leaf series, which go up to 99.999% purity. A 100% pure bullion is nearly impossible: as the percentage of impurities diminishes, it becomes progressively more difficult to purify the metal further. Historically, coins had a certain amount of weight of alloy, with the purity a local standard. The Krugerrand is the first modern example of measuring in "pure gold": it should contain at least 12/11 ounces of at least 11/12 pure gold. Other bullion coins (for example the British Sovereign) show neither the purity nor the fine-gold weight on the coin but are recognized and consistent in their composition. Many coins historically showed a denomination in currency (example: American double eagle: $20).


Philharmoniker 99 front
1 oz Vienna Philharmonic gold coin

Many nations mint bullion coins. Although nominally issued as legal tender, these coins' face value as currency is far below that of their value as bullion. For instance, Canada mints a gold bullion coin (the Gold Maple Leaf) at a face value of $50 containing one troy ounce (31.1035 g) of gold—as of May 2011, this coin is worth about 1,500 CAD as bullion.[2] Bullion coins' minting by national governments gives them some numismatic value in addition to their bullion value, as well as certifying their purity.

One of the largest bullion coins in the world was the 10,000-dollar Australian Gold Nugget coin minted in Australia which consists of a full kilogram of 99.9% pure gold. In 2012, the Perth Mint produced a 1-tonne coin of 99.99% pure gold with a face value of $1 million AUD, making it the largest minted coin in the world with a gold value of around $50 million AUD.[3] China has produced coins in very limited quantities (less than 20 pieces minted) that exceed 8 kilograms (260 ozt) of gold. Austria has minted a coin containing 31 kg of gold (the Vienna Philharmonic Coin minted in 2004 with a face value of 100,000 euro). As a stunt to publicise the 99.999% pure one-ounce Canadian Gold Maple Leaf series, in 2007 the Royal Canadian Mint made a 100 kg 99.999% gold coin, with a face value of $1 million, and now manufactures them to order, but at a substantial premium over the market value of the gold.[4][5]

Economic use

Gold Bars
1 kg gold bullion (ingots)

Gold and silver, and sometimes other precious metals, are often seen as hedges against both inflation and economic downturn. Silver coins have become popular with collectors due to their relative affordability, and, unlike most gold and platinum issues which are valued based upon the markets, silver issues are more often valued as collectibles, far higher than their actual bullion value.[6]


An initially precious metal that became common is aluminium. While aluminium is the third most abundant element and most abundant metal in the Earth's crust, it was at first found to be exceedingly difficult to extract the metal from its various non-metallic ores. The great expense of refining the metal made the small available quantity of pure aluminium more valuable than gold.[7] Bars of aluminium were exhibited at the Exposition Universelle of 1855,[8] and Napoleon III's most important guests were given aluminium cutlery, while those less worthy dined with mere silver.[7] In 1884, the pyramidal capstone of the Washington Monument was cast of 100 ounces of pure aluminium. By that time, aluminium was as expensive as silver.[9] The statue of Anteros atop the Shaftesbury Memorial Fountain (1885–1893) in London's Piccadilly Circus is also of cast aluminium. Over time, however, the price of the metal has dropped. The dawn of commercial electric generation in 1882 and the invention of the Hall–Héroult process in 1886 caused the price of aluminium to drop substantially over a short period of time.

Rough world market price ($/kg)

metal mass
Valuable metal price (US$/kg)
10 Apr 2009
22 Jul 2009
7 Jan 2010
31 Dec 2014
16 Jul 2018
Rhodium 1 39,680 46,200 88,415 39,641 77,804[15]
Platinum 5 42,681 37,650 87,741 38,902 28,960
Gold 4 31,100 30,590 24,317 38,130 43,764
Palladium 15 8,430 8,140 13,632 25,559 32,205
Iridium 1 14,100 12,960 13,117 15,432 46,940[16]
Osmium 1.5 13,400 12,200 12,217 12,217
Rhenium 0.7 7,400 7,000 6,250 2,425
Ruthenium 1 2,290 2,730 5,562 1,865 8,423[17]
Germanium 1,500 1,050[18] 1038
Beryllium 2,800 850
Silver 75 437 439 588 441 556
Indium 50[19] 325[18] 520
Gallium 19,000 580 425[18] 413
Tellurium 1 158.70
Bismuth 8.5 15.40 18.19
Mercury 85 18.90 15.95

See also


  1. ^ Platinum Guild: Applications Beyond Expectation Archived 2009-05-03 at the Wayback Machine
  2. ^ Gold prices ran around 940 USD in July 2009 according to Kitco Historical Gold Charts and Data. The USD to CAD exchange rate averaged 1.129 in July 2009 according to OANDA Historical Exchange Rates. Although the exact moment that the $1075 figure was determined is unknown, it may be considered a reasonable value for the time.
  3. ^ "1 Tonne Gold Coin". Retrieved 23 July 2015.
  4. ^ "the Greatest coined gold in the world". Retrieved 23 July 2015.
  5. ^ UKBullion (2014). "100kg Fine Gold Coin". Retrieved 2014-03-18.
  6. ^ Aharon DY, and Qadan M. (2018-10-04). "What drives the demand for information in the commodity market?". Resources Policy. doi:10.1016/j.resourpol.2018.09.013. ISSN 0301-4207.
  7. ^ a b Geller, Tom (2007). "Aluminum: Common Metal, Uncommon Past". Chemical Heritage Magazine. 27 (4). Retrieved 22 March 2018.
  8. ^ Karmarsch, C. (1864). "Fernerer Beitrag zur Geschichte des Aluminiums". Polytechnisches Journal. 171 (1): 49.
  9. ^ George J. Binczewski (1995). "The Point of a Monument: A History of the Aluminum Cap of the Washington Monument". JOM. 47 (11): 20–25. doi:10.1007/bf03221302.
  10. ^ The abundance of the element, a measure for its rarity, is given in mass fraction as kg in the earth's crust (CRC Handbook). David R. Lide, ed. (2005). "Section 14, Geophysics, Astronomy, and Acoustics; Abundance of Elements in the Earth's Crust and in the Sea". CRC Handbook of Chemistry and Physics (85 ed.). Boca Raton, Florida: CRC Press.
  11. ^ Mostly taken from London Metal Exchange.
  12. ^ From the
  13. ^ From the and (mid price quoted)
  14. ^ From the
  15. ^ From
  16. ^ From
  17. ^ From
  18. ^ a b c The metal Price ($/kg)s of gallium, germanium, and indium are taken from as examples of modern precious metals used for investment / speculation.
  19. ^ Tolcin A. (2012) U.S. Geological Survey Mineral Commodity Summaries 2012.

External links

Base metal

A base metal is a common and inexpensive metal, as opposed to a precious metal such as gold or silver. A long-time goal of alchemists was the transmutation of a base (low grade) metal into a precious metal. In numismatics, coins often derived their value from the precious metal content; however, base metals have been also used in coins in the past and today.

Billon (alloy)

Billon is an alloy of a precious metal (most commonly silver, but also mercury) with a majority base metal content (such as copper). It is used chiefly for making coins, medals, and token coins.

The word comes from the French bille, which means "log".

Britannia silver

Britannia silver is an alloy of silver containing 11 ozt 10 dwt (i.e. 11½ troy oz.) silver in the pound troy, equivalent to ​23⁄24, or 95.833% by weight (mass) silver, the rest usually being copper.

This standard was introduced in England by Act of Parliament in 1697 to replace sterling silver (92.5% silver) as the obligatory standard for items of "wrought plate". The lion passant gardant hallmark denoting sterling was replaced with "the figure of a woman commonly called Britannia", and the leopard's head mark of the Worshipful Company of Goldsmiths replaced with a "lion's head erased".Britannia standard silver was introduced as part of the great recoinage scheme of William III from 1696, when attempts were made to limit the clipping and melting of sterling silver coinage. A higher standard for wrought plate meant that sterling silver coins could not easily be used as a source of raw material because additional fine silver, which was in short supply at the time, would have to be added to bring the purity of the alloy up to the higher standard.

Britannia silver is considerably softer than sterling, and after complaints from the trade, sterling silver was again authorised for use by silversmiths from 1 June 1720, and thereafter Britannia silver has remained an optional standard for hallmarking in the United Kingdom and Ireland.Since the hallmarking changes of 1 January 1999, Britannia silver has been denoted by the millesimal fineness hallmark 958, with the symbol of Britannia being applied optionally.

The silver bullion coins of the Royal Mint issued since 1997, known as "Britannias" for their reverse image, were minted in Britannia standard silver until 2012, when they switched to 999 pure silver.

Britannia silver should be distinguished from Britannia metal, a pewter-like alloy containing no silver.

Choquequirao Puquio

Choquequirao Puquio (possibly from Quechua chuqi metal, every kind of precious metal / gold ( 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 in three groups:

Alloys with silver and copper in various proportions, producing white, yellow, green and red golds. These are typically malleable alloys.

Intermetallic compounds, producing blue and purple golds, as well as other colors. These are typically brittle, but can be used as gems and inlays.

Surface treatments, such as oxide layers.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%).

Crown gold

Crown gold is a 22 karat (kt) gold alloy used in the crown coin introduced in England in 1526 (by Henry VIII). In this alloy, the proportion of gold is 22 parts out of 24 - or 91.667% gold - and is appreciably less prone to wear than the softer 23 kt gold

of earlier gold sovereigns - an important point for coin intended for everyday use in circulation.

Decibel (magazine)

Decibel is a monthly heavy metal magazine published by the Philadelphia-based Red Flag Media since October 2004. Its sections include Upfront, Features, Reviews, Guest Columns and the Decibel Hall of Fame. The magazine's tag-line is currently "Extremely Extreme" (previously "The New Noise"); the editor-in-chief is Albert Mudrian.


Electrum is a naturally occurring alloy of gold and silver, with trace amounts of copper and other metals. It has also been produced artificially, and is often known as green gold. The ancient Greeks called it 'gold' or 'white gold', as opposed to 'refined gold'. Its colour ranges from pale to bright yellow, depending on the proportions of gold and silver.

The gold content of naturally occurring electrum in modern Western Anatolia ranges from 70% to 90%, in contrast to the 45–55% of gold in electrum used in ancient Lydian coinage of the same geographical area. This suggests that one reason for the invention of coinage in that area was to increase the profits from seigniorage by issuing currency with a lower gold content than the commonly circulating metal. (See also debasement.)

Electrum was used as early as the third millennium BCE in Old Kingdom of Egypt, sometimes as an exterior coating to the pyramidions atop ancient Egyptian pyramids and obelisks. It was also used in the making of ancient drinking vessels. The first metal coins ever made were of electrum and date back to the end of the 7th century or the beginning of the 6th century BCE. For several decades, the medals awarded with the Nobel Prize have been made of gold-plated green gold.

Essel Group

Essel Group is an Indian conglomerate company presently headed by Dr. Subhash Chandra, based in Mumbai, Maharashtra, and established in 1926.


The fineness of a precious metal object (coin, bar, jewelry, etc.) represents the weight of fine metal therein, in proportion to the total weight which includes alloying base metals and any impurities. Alloy metals are added to increase hardness and durability of coins and jewelry, alter colors, decrease the cost per weight, or avoid the cost of high-purity refinement. For example, copper is added to the precious metal silver to make a more durable alloy for use in coins, housewares and jewelry. Coin silver, which was used for making silver coins in the past, contains 90% silver and 10% copper, by mass. Sterling silver contains 92.5% silver and 7.5% of other metals, usually copper, by mass.

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 = ​18⁄24 = 75% and 24 karat gold is considered 100% gold.


A hallmark is an official mark or series of marks struck on items made of metal, mostly to certify the content of noble metals—such as platinum, gold, silver and in some nations, palladium. In a more general sense, the term hallmark can also be used to refer to any distinguishing characteristic.

Metal clay

Metal clay is a crafting medium consisting of very small particles of metal such as silver, gold, bronze, or copper mixed with an organic binder and water for use in making jewelry, beads and small sculptures. Originating in Japan in 1990, metal clay can be shaped just like any soft clay, by hand or using molds. After drying, the clay can be fired in a variety of ways such as in a kiln, with a handheld gas torch, or on a gas stove, depending on the type of clay and the metal in it. The binder burns away, leaving the pure sintered metal. Shrinkage of between 8% and 30% occurs (depending on the product used). Alloys such as bronze, sterling silver, and steel also are available.

Metallurgical assay

A metallurgical assay is a compositional analysis of an ore, metal, or alloy.

Some assay methods are suitable for raw materials; others are more appropriate for finished goods. Raw precious metals (bullion) are assayed by an assay office. Silver is assayed by titration, gold by cupellation and platinum by inductively coupled plasma optical emission spectrometry (ICP OES).

Precious metal items of art or jewelry are frequently hallmarked (depending upon the requirements of the laws of either the place of manufacture or the place of import). Where required to be hallmarked, semi-finished precious metal items of art or jewelry pass through the official testing channels where they are analyzed or assayed for precious metal content. While different nations permit a variety of legally acceptable finenesses, the assayer is actually testing to determine that the fineness of the product conforms with the statement or claim of fineness that the maker has claimed (usually by stamping a number such as 750 for 18k gold) on the item. In the past the assay was conducted by using the touchstone method but currently (most often) it is done using X-ray fluorescence (XRF). XRF is used because this method is more exacting than the touchstone test. The most exact method of assay is known as fire assay or cupellation. This method is better suited for the assay of bullion and gold stocks rather than works of art or jewelry because it is a completely destructive method.

Methods of coin debasement

Coin debasement is the act of decreasing the amount of precious metal in a coin, while continuing to circulate it at face value. This was frequently done by governments in order to inflate the amount of currency in circulation; typically, some of the precious metal was replaced by a cheaper metal when the coin was minted. But when done by an individual, precious metal was physically removed from the coin, which could then be passed on at the original face value, leaving the debaser with a profit. Coin debasement was effected by several methods, including clipping (shaving metal from the coin's circumference) and sweating (shaking the coins in a bag and collecting the dust worn off).

Until the mid-20th century, coins were often made of silver or gold, which were quite soft and prone to wear. This meant coins naturally got lighter (and thus less valuable) as they aged, so coins that had lost a small amount of bullion would go unnoticed. Modern coins are made of hard, cheap metals such as steel, copper, or a copper-nickel alloy, reducing wear and making it difficult and unprofitable to debase them.

Clipping is the act of shaving off a small portion of a precious metal coin for profit. Over time, the precious metal clippings could be saved up and melted into bullion or used to make new coins.Coin clipping was usually considered by the law to be of a similar magnitude to counterfeiting, and was occasionally punished by death, a fate which befell English counterfeiters Thomas Rogers and Anne Rogers in 1690.

Coin clipping is why many coins have the rim of the coin marked with stripes (milling or reeding), text (engraving) or some other pattern that would be destroyed if the coin were clipped. This practice is attributed to Isaac Newton, who was appointed Master of the Mint in 1699. Although the metal used in most modern fiat coins has insignificant intrinsic value, modern milling can be a deterrent to counterfeiting, an aid to the blind to distinguish different denominations, or purely decorative.

In the process of sweating, coins were placed in a bag and shaken. The bits of metal that had worn off the coins were recovered from the bottom of the bag. Sweating tended to wear the coin in a more natural way than clipping, and so was harder to detect.If the coin was large, a hole could be punched out of the middle, and the face of the coin hammered to close up the hole. Or the coin could be sawed in half, and a plug of metal extracted from the interior. After filling the hole with a cheaper metal, the two halves would be welded back together again. Verbal references to plugged quarters and plugged dimes eventually yielded the common phrase "not worth a plugged nickel" (or 'plug nickel', or even a plugged cent), emphasizing the worthlessness of such a tampered coin.

Michael Morley (musician)

Michael Morley is an experimental musician and visual artist from New Zealand.

Morley sings and plays guitar and laptop as a member of The Dead C, but also records on his own (and with collaborators) as Gate. Earlier, in the 1980s, Morley was a member of Wreck Small Speakers On Expensive Stereos.Morley founded the Precious Metal label sometime in the late 1980s to document, first on cassette and later LP and CD, his own work as Gate. Most of the releases on Precious Metal were limited to very small quantities.

Morley currently teaches at Otago Polytechnic School of Art in Dunedin.


Orichalcum or aurichalcum is a metal mentioned in several ancient writings, including the story of Atlantis in the Critias of Plato. Within the dialogue, Critias (460 – 403 BC) claims that orichalcum had been considered second only to gold in value and had been found and mined in many parts of Atlantis in ancient times, but that by Critias' own time orichalcum was known only by name.

Orichalcum may have been a noble metal such as platinum, as it was supposed to be mined, or one type of bronze or brass or possibly some other metal alloy. In 2015, metal ingots were found in an ancient shipwreck in Gela (Sicily), which were made of an alloy primarily consisting of copper, zinc and small percentages of nickel, lead, and iron.In numismatics, orichalcum is the golden-colored bronze alloy used by the Roman Empire for their sestertius and dupondius coins.


Shakudō (赤銅) is a Japanese billon of gold and copper (typically 4–10% gold, 96–90% copper), one of the irogane class of colored metals, which can be treated to develop a black, or sometimes indigo, patina, resembling lacquer. Unpatinated shakudō visually resembles bronze; the dark color is induced by the niiro artificial patination process, involving boiling in a solution, generally including rokushō.


Shibuichi (四分一) is a historically Japanese copper alloy, a member of the irogane class, which is patinated into a range of subtle greys and muted shades of blue, green, and brown, through the use of niiro processes, involving the rokushō compound.


Tumbaga is the name for a non-specific alloy of gold and copper given by Spanish Conquistadors to metals composed of these elements found in widespread use in pre-Columbian Mesoamerica and South America.

The term is believed to be a borrowing from Malay tembaga, meaning "copper" or "brass", which in turn is from Prakrit.


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