Precious metals
A precious metal is a chemical element metallic rare and of great economic value.
The notion of precious metal fluctuates according to the times and the civilizations depending on supply and demand: today the value is allocated to gold, the platinum, the rhodium and the palladium, silver.
Precious metals play a crucial role in the global economy, serving as a safe haven in times of economic uncertainty, hence the increase in their prices in recent years.
List of metals in order of preciousness
Rhodium: The most expensive and rarest metal. Belongs to the platinum group of metals. Resists oxidation and corrosion. Melting point at 2000 degrees.
Palladium: silvery white, belongs to the platinum group of metals.
Requires no surface treatment.
Gold: yellow, white, gray or pink, depending on the alloys. Noble metal and for 24 carats, very malleable and soft. That 18 carats is used in jewelry-jewelry
Platinum: bright white, very hard, resistant metal, used for precious alloys
Silver: solid, 925/1000, very widespread and widely used in jewelry.
Titanium: silver-gray semi-precious metal, can be plated. It is known for its hypoallergenic, robust and lightweight properties.
Vermeil: semi-precious metal because it contains a deposit of 18 carat gold of a minimum of 3 microns on solid silver
For more information: https://ocarat.com/guide/
Precious metals ingots - photo credit Mondial-infos.fr
History
Over the centuries, precious metals have been used in many areas, jewelry, coins, art objects.
At the time of the Ancient Greece, the Corinthian bronze was an alloy considered more precious than gold or silver.
In the Ottoman Empire, under Suleiman the Magnificent, the goldsmiths applied themselves to embedding ruby and emeralds of the teapots in zinc.
This dull metal was then almost unknown and therefore considered very rare.
At 19th century Again, platinum was used by scammers to counterfeit certain gold coins (platinum having the same density as gold).
In the years 1860, the Discovery of silver veins in the American West makes this metal superabundant, affecting the economy of nations using a monetary system based on bimetallism.
Use
Precious metals have many industrial applications. In particular, electronics uses platinum, palladium, rhodium, gold and silver. Precious metals are also essential for the medical sector (prosthetics).
The production of these metals by extraction from the natural environment is no longer sufficient to meet the needs of global consumption.
For gold, whose production has been falling since 2001, it is estimated that 10 to 20% of consumption comes from recycling
Title of precious metals
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Measurement of metal content |
· Title (metal) · Title to the thousandth · Carat (purity) |
|
|
Control procedure |
· Acid test · Touchstone · Cupellation |
|
The CARAT
There are two types of "carats"
The carat of precious metal is a unit of measurement to express its purity.
| Carat titration | Percentage of gold in thousandths |
| 24 carat gold | 999.9 ‰ |
| 22 carat gold | 916 ‰ |
| 19 carat gold | 800 ‰ |
| 18 carat gold | 752 ‰ |
| 14 carat gold | 585 ‰ |
| 12 carat gold | 500 ‰ |
| 10 carat gold | 417 ‰ |
| 9 carat gold | 375 ‰ |
| 8 carat gold | 333 ‰ |
THE carat in gemology is a unit of weight
One carat is equal to one-fifth of a gram (0.20 grams), or 5 carats = 1 gr gram