Elements for Kids Platinum

Elements for Kids Platinum

<—Iridium       Gold—>

Symbol: Pt

Atomic Number: 78

Atomic Weight: 195.084

Classification: Transition metal Phase at Room Temperature: Solid Density: 21.45 grams per cm cubed Melting Point: 1768°C, 3215°F Boiling Point: 3825°C, 6917°F Discovered by: Peoples of South America Platinum is the third element of the tenth column in the periodic table. It is classified as a transition metal. Platinum atoms have 78 electrons and 78 protons with 117 neutrons in the most abundant isotope. It is considered to be a precious metal along with silver and gold. Characteristics and Properties Under standard conditions platinum is a shiny, silvery metal. It is very ductile, meaning that it can be easily stretched into a wire. It is also malleable, meaning it can be pounded into a thin sheet. Platinum is resistant to corrosion when it comes into contact with air. It is also very dense (one of the highest of the elements) and has a high melting point. Platinum is fairly inactive, but it will dissolve in hot alkalis and aqua regia. Where is it found on Earth? Platinum is a rare metal and difficult to find. This is what makes it such a valuable metal. Platinum can be found in its pure form, but is most often found together with other metals from the platinum group. The majority of platinum is mined in South Africa with Russia coming in a distant second. How is platinum used today? Being a precious metal, platinum is often used as currency and as an investment. It is also used in coins and to make jewelry such as rings, earrings, and watches. Despite being a popular metal for jewelry, platinum is most often used as a catalyst in chemical reactions. It is used as a catalyst for the automobile and petroleum industries. Other applications for platinum include alloys for special metals, super strong magnets, medical instruments, and dental work. How was it discovered? Platinum was first found by the peoples living in South America prior to the arrival of the Spanish. They produced a platinum and gold alloy that they used in their artwork and jewelry. The first scientist to isolate platinum in its pure element form was English chemist William Hyde Wollaston in 1803. Where did platinum get its name? Platinum gets its name from the Spanish word “platina” which means “silver.” Isotopes There are six naturally occurring isotopes. The most abundant of these is Platinum-195. Interesting Facts about Platinum William Hyde Wollaston also discovered the elements palladium and rhodium. It is the most ductile of the pure metals. Only gold is more malleable. The group of metals that platinum is part of in the periodic table is sometimes called the platinum group. Its malleability allows it to be pounded into a sheet as thin as 100 atoms. The word “platinum” is often associated with wealth and value. Sometimes awards called “platinum” are considered higher than “gold.”

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Facts About Silver Jewelry And Gold Jewelry Metals/

Facts About Silver Jewelry And Gold Jewelry Metals/

What You Should Know – Silver and Gold Jewelry

About Silver Accessories and Karat Gold Jewelry

The two precious metals most often used in jewelry are alloys of silver and gold.

There are many different alloys used in modern jewelry making.

The type of jewelry you can wear is not just determined by your wallet –
but also by the way your body reacts to and tolerates exposure to metals.

Sterling silver tarnishes, especially in hot, humid weather. It contains 7.5% copper
by weight, which reacts with common air pollutants, darkening the surface of the metal.

This can prompt skin irritation if your skin is sensitive to (usually) nickel or Fats about (sometimes) copper.

If you have noticed that you have an itch that persists with drying and reddening of your
skin where your jewelry touches it, you are probably sensitive to the alloy in the metal.

Gold and silver are known to be non – reactive metals; but that does not mean
that everyone can wear any type of gold or silver jewelry without any problem.

Understanding more about metals can help you to choose
jewelry that is more comfortable and healthy for you to wear!

Higher karat gold alloys tend to be better tolerated than lower karat qualities because there is
less of the reactive metal in the alloy. Many people wear 18K or 22K gold jewelry for this reason.

Sterling silver is .925 pure, or 92.5% silver by weight, a very high percentage.
Most people don’t have any problems wearing sterling silver jewelry.

Modern silver alloys don’t contain nickel, the usual irritant in jewelry metals. Lower percentage
silver alloys like vintage “European” silver can irritate your skin more easily than sterling silver jewelry
if you have copper sensitive skin, because old European silver is .800 fine, or 80% silver / 20% copper.

Following is a listing of metals commonly used in jewelry making and an explanation of their properties.


Gold Facts – Alloys, Karats, and more!

Pure 24K gold is hypoallergenic. It doesn’t cause irritation to the body.

However, the metals mixed with gold to make it harder or
enhance the color of gold can cause adverse skin reactions.

Gold is very malleable, meaning it can be hammered
into very thin sheets – thin enough for light to pass through.

Gold is also very ductile – it can be pulled
through drawplates into wire much thinner than hair.

Pure gold is very soft. It is very easy to work with hand tools.To make it harder
it is mixed with other metals, creating an alloy. Gold alloy purity is expressed in karats.

Gold alloys are available in many colors. The color of the alloy is determined
by the percentage and type(s) of metal “mixed” with the pure gold.

Rose gold contains more copper; until recently
white gold was traditionally made with nickel.

Now white gold is also made with palladium, a platinum
family metal; green gold is made with an alloy of fine silver.
As an example, most green gold is 18 karat; 75% gold, 25% silver.

There are MANY other colors made with alloy combinations.

The percentage of gold used is directly related to the karat content of the alloy.

It does not matter what type of metal is “mixed” with the gold, just how much.

The chart (below) shows how much gold is in your jewelry.


1k Gold = 4.17% Gold and 95.83% alloy

2k Gold = 8.33% Gold and 91.67% alloy

3k Gold = 12.5% Gold and 87.5% alloy

4k Gold = 16.67% Gold and 83.33% alloy

5k Gold = 20.83% Gold and 79.17% alloy

6k Gold = 25% Gold and 75% alloy

7k Gold = 29.17% Gold and 70.83% alloy

8k Gold = 33.3% Gold and 66.67% alloy

9k Gold = 37.5% Gold and 62.5% alloy

10k Gold = 41.67% Gold and 58.33% alloy

11k Gold = 45.83% Gold and 54.17% alloy

12k Gold = 50% Gold and 50% alloy

13k Gold = 54.17% Gold and 45.83% alloy

14k Gold = 58.33% Gold and 41.67% alloy

15k Gold = 62.5% Gold and 37.5% alloy

16k Gold = 66.67% Gold and 33.33% alloy

17k Gold = 70.83% Gold and 29.17% alloy

18k Gold = 75% Gold and 25% alloy

19k Gold = 79.1% Gold and 20.83% alloy

20k Gold = 83.33% Gold and 16.67% alloy

21k Gold = 87.5% Gold and 12.5% alloy

22k Gold = 91.67% Gold and 8.33% alloy

23k Gold = 95.83% Gold and 4.17% alloy

24k Gold = 100% Gold and 0% alloy


In this chart, “alloy” means the other metal. It can be
silver, copper, zinc, nickel, iron or almost any other metal.

For instance, 10 karat yellow gold is 41.67% pure gold and 58.33% “other metals”,
mostly copper, maybe some silver and most likely some nickel or zinc to add hardness.

In the United States gold must be at least 9K to be sold as karat gold.

Lower karat gold alloys have a  higher percentage of the other metals added to them.

They tend to react to the pollutants and other
impurities in the air faster than higher karat gold alloys.

This means that the high percentage of copper or other metal in the
lower karat alloy will tarnish (or oxidize), just like sterling silver items do.

This can occur especially in hot weather when the metals react to salt in perspiration.

If this happens to your sterling silver or lower karat gold jewelry, you may want to take it off
and wash the piece in hot water with a detergent like Dawn, Joy or whatever you prefer.

If your jewelry is really dirty, try scrubbing it carefully with a soft toothbrush.
Polish with a jewelry polishing cloth, if you have one. Rinse and dry before wearing.

If you have a problem with sterling silver, medium to
low karat gold will probably give you difficulties as well.

Medium to low karat yellow gold has a much higher percentage of copper in it than sterling silver.

Nickel allergies are the most common. Many people have problems wearing white gold –
the problem isn’t the gold. It’s actually nickel – the alloy – that causes skin reactions!

The new palladium white gold alloys are a bit more expensive, but are hypoallergenic.


Silver Jewelry Metal Facts

Sterling silver is generally used for jewelry, and that is what most people think of when they see silver.

Silver also comes in various quality grades, measured by 1/1000 parts per gram.

There are impurities that naturally occur in silver at the molecular level. These impurities
consist of other metals – usually copper, but traces of other metals can also be found.

These trace impurities are insignificant, and would be
too costly to remove – so .999 silver is considered pure.

The table (below) shows the types of silver alloys generally used in jewelry making.

Silver Alloys

.999 
fine silver

Contains .001 trace metals.

.9584
Britannia

95.84% silver + 4.16% copper.

.925
sterling

92.5% silver + 7.5% copper.

.900
coin

90% silver + 10% copper.

.830
European

83% silver + 17% copper.

.800
European

80% silver + 20% copper.

All the alloys shown are legally referred to as “silver”.

The only legal requirement is that they are quality stamped or marked for sale to the public.

Silver Facts

As with gold, silver in its fine state is a non – reactive metal – allergies are possible but VERY rare.

People who have problems wearing silver jewelry are usually
allergic to the copper in the alloyed metal, not the silver.

During the European Industrial Revolution, people found that their .800 silver was tarnishing
much faster than before – a reaction to the new pollutants in the air – from burning coal in the factories!

Fine, or pure, silver with no copper content does not tarnish easily. Think about the fine silver
coins brought up from wrecked ships – everything from the Atocha to sunken pirate ships.

They come up out of the ocean after hundreds of years bright and shiny as new.

Fine silver can get dirty, of course, but will not tarnish like sterling silver.

There is a new alloy called Argentium® Silver. It is sterling, but contains germanium in place of copper.

Argentium® doesn’t develop firescale as easily during soldering and doesn’t tarnish the way
traditional sterling silver does because the germanium doesn’t react as the copper does.


Plated and Filled

There are different grades and methods of bonding precious metals to
a less expensive base metal, as indicated in the chart below.

Finished, Washed, Colored

These terms refer to the thinnest gold, silver, platinum or rhodium coatings. 
There is no standard thickness.

Plated, Electroplated

These metals have a required minimum standard thickness – usually .15 – .25 mils

Gold, Platinum or Silver Filled metals

A layer of karat gold, platinum or silver is mechanically
bonded to a base metal, usually brass or steel.

Filled metals usually have a thickness over 100 times that of plated metals.

Gold filled may be  marked with the gold percentage by weight and the karat value.

If a piece of jewelry is marked 1/20 14K GF – 5% of the total weight is 14K gold.
However, this is not required by law. Most times the quality is stated on a hang tag.

There is no approved marking system in the US for filled metals.

 Vermeil Gold plated over silver

Silver is the “base” metal

Many jewelry items are made of either plated or filled metals.

This is done to keep the cost of these items as low as possible.

The whole piece can be plated or filled metal, as with a chain. In many cases, the clasp and
metal parts of an otherwise top quality gemstone bead necklace or bracelet can be plated or filled.

If it is taken care of and worn properly, such as over a sweater, a necklace with plated parts
can last for a very reasonable length of time, even years – but eventually the plated
metal parts will oxidize or the plating will wear through to the base metal.

Filled metals are much higher quality and a much longer useful lifespan.

They have one or more layers of precious metal bonded to a base with heat and pressure.

Filled materials are at least 1/20 precious metal by weight.

They are much longer lasting than ordinary plated objects.

Filled metal objects are not usually marked with a quality stamp, such as 12k GF or 14k GF.

For information on the care and cleaning of jewelry, please visit this article:Jewelry Care

Article written by Robert Edwards ©2015.
Robert is a jeweler and metalsmith, and is webmaster of http://www.jewelry24seven.com.

This article may be linked and used as content on blogs and websites conditionally … ALL content –
links, author, copyright – must not be changed in ANY way – it must appear exactly as the article appears above.

 

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Precious metal

Precious metal

From Wikipedia, the free encyclopedia

Assortment of noble metals

precious metal is a rare, naturally occurring metallicchemical 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 commoditiesGoldsilverplatinum, 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 artjewelry, fine jewelry and coinage. Other precious metals include the platinum group metals: rutheniumrhodiumpalladiumosmiumiridium, 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.

Bullion[edit]

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[edit]

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.[citation needed] Many coins historically showed a denomination in currency (example: American double eagle: $20).

Coinage[edit]

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.[citation needed]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 Mintmade 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[edit]

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.

Aluminium[edit]

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.[6] Bars of aluminium were exhibited at the Exposition Universelle of 1855,[7] and Napoleon III‘s most important guests were given aluminium cutlery, while those less worthy dined with mere silver.[6] 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.[8] 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)[edit]

Valuable metal price ($/kg) with precious metal names in bold
metal mass abundance
parts per billion[9]
10 April 2009[10] 22 July 2009[11] 7 January 2010[citation needed] 31 December 2014[12]
Rhodium 1 39680 46200 88415 39641
Platinum 5 42681 37650 87741 38902
Gold 4 31100 30590 24317 38130
Palladium 15 8430 8140 13632 25559
Iridium 1 14100 12960 13117 15432
Osmium 1.5 13400 12200 12217 12217
Rhenium 0.7 7400 7000 6250 2425
Ruthenium 1 2290 2730 5562 1865
Germanium 1500 1050[13] 1038
Beryllium 2800 850[citation needed]
Silver 75 437 439 588 441
Gallium 19000 580 425[13] 413
Indium 50[14] 325[13] 520
Tellurium 1 158.70
Mercury 85 18.90 15.95
Bismuth 8.5 15.40 18.19
  1.  Platinum Guild: Applications Beyond Expectation
  2. Jump up^ 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 $1075 figure was determined is unknown, it may be considered a reasonable value for the time.
  3. Jump up^ “1 Tonne Gold Coin”perthmint.com.au. Retrieved 23 July2015.
  4. Jump up^ “the Greatest coined gold in the world”e-allmoney.com. Retrieved 23 July 2015.
  5. Jump up^ UKBullion (2014). “100kg Fine Gold Coin”. Retrieved 2014-03-18.
  6. Jump up to:a b Geller, Tom (2007). “Aluminum: Common Metal, Uncommon Past”Chemical Heritage Magazine27 (4). Retrieved 7 December 2016.
  7. Jump up^ Karmarsch, C. (1864). “Fernerer Beitrag zur Geschichte des Aluminiums”Polytechnisches Journal171 (1): 49.
  8. Jump up^ George J. Binczewski (1995). “The Point of a Monument: A History of the Aluminum Cap of the Washington Monument”JOM47 (11): 20–25. doi:10.1007/bf03221302.
  9. Jump up^ The abundance of the element, a measure for its rarity, is given in mass fraction as kg in the earth’s crust (CRC Handbook). David R. Lide, ed. (2005). “Section 14, Geophysics, Astronomy, and Acoustics; Abundance of Elements in the Earth’s Crust and in the Sea”. CRC Handbook of Chemistry and Physics (85 ed.). Boca Raton, Florida: CRC Press.
  10. Jump up^ Mostly taken from London Metal Exchange.
  11. Jump up^ From the http://www.thebulliondesk.com/
  12. Jump up^ From the http://www.thebulliondesk.com and http://www.taxfreegold.co.uk (mid price quoted)
  13. Jump up to:a b c The metal Price ($/kg)s of gallium, germanium, and indium are taken from MinorMetals.com as examples of modernprecious metals used for investment / speculation.
  14. Jump up^ Tolcin A. (2012) U.S. Geological Survey Mineral Commodity Summaries 2012.

External links[edit]