Gold
Anonymous. Metal Bulletin Monthly 418 (Oct 2005): 50-51.

Abstract (summary)

Pure - or 1,000 thousandths - gold is equivalent to 24 carats, but gold is generally used as an alloy because it is such a soft metal. The jewellers' terms "fine gold" and "pure gold" mean 920 and 840 thousandth alloys respectively, the balance being supplied by copper. The addition of copper produces red and pink golds, while deep yellow gold is practically 100% pure and "white gold" is often a gold alloy containing nickel and palladium.
Pure - or 1,000 thousandths - gold is equivalent to 24 carats, but gold is generally used as an alloy because it is such a soft metal. The jewellers' terms "fine gold" and "pure gold" mean 920 and 840 thousandth alloys respectively, the balance being supplied by copper. The addition of copper produces red and pink golds, while deep yellow gold is practically 100% pure and "white gold" is often a gold alloy containing nickel and palladium.
Full Text

Gold is among the oldest metals known to mankind, over whom it has often exerted a compelling force of attraction because of its rarity, lustrous beauty and permanence.
A sun-yellow ductile metallic element, gold mostly occurs as nuggets in rocks and alluvial deposits. It has a high melting point (1,063°C) and is one of the best conductors of heat and electricity, as well as being resistant to corrosion, except from chlorine, fluorine and aqua regia acid. It is one of the densest elements at 19.3 g/cm^sup 3^.
Scattered in low concentrations across the Earth's crust and in sea water, gold often occurs in non-recoverable trace quantities. It is mainly found as native gold or in copper ores, and occasionally as telluride (AuAgTe^sub 4^).
Native deposits called lode gold are found in high temperature hydrothermal quartz veins or as alluvial deposits known as placers, which originate from eroded gold-bearing rocks. Native gold often contains silver and platinum group metals.
History
The chemical symbol for gold, Au, is derived from the Latin word "aurum," meaning shining dawn. Artisans of ancient civilisations used gold lavishly to adorn tombs and temples; famous examples are the funeral masks of the Egyptian pharaohs Tutankhamen and Psusennes.
In the 16th century, the Spanish Conquistadores' insatiable desire to hoard the gold they discovered in South America led to the annihilation of entire native tribes. During the 19th century, gold rushes occurred whenever large gold deposits were found, for instance in 1834 at the Witwatersrand in South Africa and in 1896 at Klondike in north-western Canada - the latter deposits were exhausted by 1910.

The quest for gold led early alchemists unsuccessfully to attempt to make gold from base metals such as lead and copper. During the 1950s, gold synthesis was achieved at great financial cost through the nuclear irradiation of mercury or platinum.
In the 19th and 20th centuries, gold played a key role in international monetary transactions until the collapse of the 1944 Bretton Woods agreement in 1972. The international gold standard was adopted in 1871 to back currencies; most of the bullion produced each year went into the vaults of government treasuries or central banks, many of which still retain at least some gold reserves.
Production
Initially, gold was extracted by using gravity to separate the dense metal from the ore or quartz gangue. The origins of the mythological "Golden Fleece" may lie with the sheep skins sometimes used to retain gold particles, then burnt to recover the metal. Other subsequent small-scale agitating and collecting devices include the gold pan, rocker and sluice box.

Around 500 BC, mercury was used to collect the gold in a form of amalgam; the end product was then recovered by distillation. At the end of the 19th century, cyanide leaching to extract gold was introduced in South Africa. This process allowed gold to be recovered from low-grade ores, as well as from the tailings from earlier workings. The ores are dissolved in an alkaline cyanide solution and the gold is then recovered by cementation with zinc. Zinc is removed from the cement by sulphuric acid leaching and melted in the presence of borax to produce the alloy bullion, which is subsequently refined.
Gold can also be separated through a carbon-in-pulp process, whereby the cyanide/gold mix is precipitated on carbon columns. Sulphide ores need to be converted to oxide by roasting before cyanide leaching.
World production of gold from ore in 2004 was estimated at 2,464.4 tonnes, plus 828 tonnes recovered from scrap, according to UK analysts GFMS. South Africa remains the major gold producer, with the USA and Australia vying for second position. Global mine production dropped by 129 tonnes last year, the steepest decline in output since 1943, according to GFMS. Mine closures, harsh weather conditions, pre-stripping activities and operational delays all contributed to this drop. The biggest gold producing companies in 2004 were Newmont (USA) with 212 tonnes and AngloGold Ashanti (South Africa) with 188 tonnes (see table).
Applications
Approximately 74% of the 3,511 tonnes of gold consumed last year was used in the manufacture of jewellery, 7% went into electronics, 7% to hoarding, 4% to industrial applications, 3% to coins, 2% to dentistry and 1% to medals, reports GFMS.
Pure - or 1,000 thousandths - gold is equivalent to 24 carats, but gold is generally used as an alloy because it is such a soft metal. The jewellers' terms "fine gold" and "pure gold" mean 920 and 840 thousandth alloys respectively, the balance being supplied by copper. The addition of copper produces red and pink golds, while deep yellow gold is practically 100% pure and "white gold" is often a gold alloy containing nickel and palladium.
Gold can be beaten into semi-transparent foil or leaf only 0.01 mm thick, and drawn into a thread weighing less than 0.5 g per kilometre. Because of its excellent conductivity and corrosion resistance, minor amounts are used in electronics for wiring, connectors, contacts and some semi-conductors.
Gold is used in dentistry for fillings with the addition of platinum and palladium. Medical devices, such as pacemakers and other implants, exploit gold's electrical conductivity, stability and tendency not to react with surrounding chemicals.
Other uses include decorative gold leafing, catalytic applications and industrial reflectors used to bake in paint or other finishes.
Markets
Gold scrap flow patterns correlate to general economic trends and the price of the metal, but they are also affected by increased legislation to recycle electronic goods and improved recovery technologies. The volume of gold recovered from old jewellery, electronics and other fabricated products fell to a three-year low last year, driven by the expectation of a strong rise in price.
Since the removal of price restrictions in 1967, the price of gold rose rapidly through the 1970s, peaking at US$800 per oz in 1980. From this point the price declined and it has traded between $250 and $500 per oz subsequently. This year, prices have fluctuated according to the direction of the dollar and the price on Comex went briefly over $450 for the first time in almost nine months as investors turned to gold as a protection against possible inflation pressures created by higher energy costs, in mid-August. Gold still acts as an economic haven in times of political or economic uncertainty.

Outlook
Because gold is used in very limited quantities by industry, its industrial demand is less sensitive to price movements than other market sectors. Although electronics demand rose by a buoyant 11% during last year, the short-term outlook for this sector and in medical applications is flat. The average bonding wire diameter may decrease from 25 to 15 micron over the next five years, lowering the gold content per metre of wire by two-thirds, in response to increasingly complex integrated circuit designs.
But demand is projected to increase in jewellery markets, especially in developing economies in South Asia, where much jewellery is purchased as a form of saving. European demand is expected be low this year, while demand in the USA and Japan is forecast to rise slightly.
The New York-based CPM Group forecasts a 3% increase in gold mine production this year, bringing to a halt the five-year decline. This increase will come from Australia and Indonesia, while South African production is at its lowest level for more than 70 years because of reserve depletion and the strong rand, which has slashed miners' profits and forced the closure of marginal mines.
Copyright Metal Bulletin Journal Ltd. Oct 2005
Word count: 1291

Indexing (details)
Cite Subject Gold; Chemical elements;Mechanical properties;Applications;Market analysis;PricesLocation:United States--US Classification 9190: United States, 8500: Extractive industries Title: Gold Author:Anonymous
Publication title : Metal Bulletin Monthly Issue 418 Pages 50-51 Number of pages:2 Publication year:2005
Publication date Oct 2005 Year 2005 Section fundamentals Publisher Euromoney Trading Limited
Place of publication London Country of publication United Kingdom Journal subject Metallurgy
ISSN 03734064 CODEN MMBMFQ
Source type Trade Journals
Language of publication English
Document type Feature
Document feature
Tables;Photographs;Graphs
ProQuest document ID
204086589
Document URL: http://search.proquest.com/docview/204086589?accountid=15518
Copyright Copyright Metal Bulletin Journal Ltd. Oct 2005
Last updated 2010-06-07
Database ProQuest Central

Questions

Where is gold found in the nature?

What is the chemical symbol for gold?

What are the uses of gold?
Gold can be used as a monetary exchange, in jewelry, in modern dentistry, in electronics, in medicine, in embroidery, and in ornaments.

Who are the world’s largest producers of gold?

Why is gold so expensive?