Its chemical symbol is Pt and its atomic order is 78. Platinum is a gray precious metal with high density, high ductility and low reactivity, belonging to transition metals. According to international regulations, only platinum can be called platinum, so the two are the same thing.
This is a natural white precious metal. Originated 2 billion years ago, a huge meteorite hit the earth and brought this precious metal. As early as 700 BC, platinum was shining brilliantly in the history of human civilization. In the 2000-year history of human use of platinum, platinum has always been regarded as the noblest metal and sought after by the noble royal family.
silver
Silver, namely silver, is called silver because of its white color, as opposed to gold. Think of it as money and decorations. In ancient times, money was called silver.
Pure silver is white in color, metallic in luster with impurities, soft in quality, hardened with impurities, and grayish red in color. Pure silver has a specific gravity of 10.5, a melting point of 960.5℃, good conductivity, and is soluble in nitric acid and sulfuric acid. Silver is one of the metals found in ancient times.
Although silver also exists in the form of simple substance in nature, most of it exists in the form of combined state. Silver has high ductility, so it can be rolled into a transparent foil with a thickness of only 0.3 microns, and silver particles with a weight of 1 g can be drawn into filaments about two kilometers long.
The thermal conductivity and electrical conductivity of silver are among the best among metals.
platinum
brief introduction
Platinum is a chemical element, commonly known as platinum. Its chemical symbol is Pt and its atomic order is 78. Platinum is a gray precious metal with high density, high ductility and low reactivity, belonging to transition metals.
According to international regulations, only platinum can be called platinum, so the two are the same thing. This is a natural white precious metal. Originated 2 billion years ago, a huge meteorite hit the earth and brought this precious metal.
As early as 700 BC, platinum was shining brilliantly in the history of human civilization. In the 2000-year history of human use of platinum, platinum has always been regarded as the noblest metal and sought after by the noble royal family.
Platinum is often confused with platinum in the market. However, the English word for platinum is white gold, the main component of which is gold. After adding other metals, it is white and easy to fade. Platinum (platinum) is pure white and never fades.
characteristic
pure
Platinum jewelry has a high purity.
The purity of platinum jewelry is usually as high as 90%-95%, and the purity of common platinum jewelry is Pt900 and Pt950.
According to national regulations, only jewelry with platinum content above 85% can be called platinum jewelry. Platinum jewelry is extremely pure and will not cause skin allergies.
Platinum has a natural pure white color.
The white luster of platinum is natural and pure, giving platinum jewelry a unique appearance. Even if it is worn daily, platinum always maintains a pure white luster.
infrequent
Platinum production is very small
Platinum is 30 times rarer than gold, and it is mined in only a few places in the world. If all the platinum in the world is poured into an Olympic standard swimming pool, the depth is not enough to cover the instep, and gold can fill at least three swimming pools.
3 grams is only equivalent to the weight of a small platinum ring, and it takes about 8 weeks and a lot of energy to extract these platinum.
eternal
Platinum can be worn every day and will never change.
Platinum is very stable in nature and will not deteriorate or fade due to daily wear. Its luster will never change. Even if you come into contact with common acidic substances in life, such as sulfur in hot springs, bleach, chlorine in swimming pools, or sweat, it will not be affected, so you can wear platinum jewelry at any time with great confidence.
The natural pure white of platinum will never fade.
No matter how long it is worn, platinum can always maintain its natural pure white luster and never fade.
To classify or arrange in pairs or groups.
Platinum gives diamonds safe and lasting care.
The toughness and ductility of platinum means that even a small platinum claw can safely and firmly set every diamond. This can be proved in the classic designs of many international brands-platinum can be competent for all kinds of inlay designs and techniques, and firmly inlay every diamond of different sizes.
Platinum perfectly sets off the brilliance of diamonds.
The pure white color of platinum will not detract from the brilliance of the gem, but can truly show the fire color of the gem itself, whether it is shiny diamonds or other colorful treasures.
Platinum is the first choice for top jewelry brands.
Especially famous for the custom-made jewelry of the European royal family. Platinum and diamonds have always been the perfect presentation of these masterpieces, becoming the favorite of famous jewelry brands and the royal family.
silver
The importance of silver
Pure silver is white in color, metallic in luster with impurities, soft in quality, hardened with impurities, and grayish red in color.
The melting point is 96 1.93℃, the boiling point is 22 12℃ and the density is 10.5g/cm3 (20℃). Silver is soft, flexible and malleable, second only to gold. It can be pressed into sheets and drawn into filaments.
Soluble in nitric acid and sulfuric acid. The reflectivity of silver to light reaches 9 1%. At room temperature, halogen can slowly combine with silver to form silver halide. Silver does not react with dilute hydrochloric acid, dilute sulfuric acid and alkali, but can react with strong oxidizing acid concentrated nitric acid and concentrated hydrochloric acid.
The main uses of silver are mainly based on three pillars: industry, photography and jewelry and silverware. The total demand of these three types of silver accounts for about 85% of the demand for silver.
Since ancient times, silver and gold have been regarded as a symbol of wealth together. The chemical symbol of silver is Ag, which comes from the Latin Argertum, meaning "light and brightness". Because silver is white, it is called "silver".
Silver not only has good electrothermal conductivity, but also has high photosensitivity and luminous characteristics, and is used in industry, photography, jewelry, currency manufacturing and so on.
The history of silver
In ancient times, people knew about silver.
Like gold, silver is a precious metal with a long history of application, which has a history of more than 4,000 years. Because of the unique excellent characteristics of silver.
People have given it the dual value of money and decoration. The pound and silver dollar used before liberation in China are mainly silver and copper alloys. 1 silver in Qing dynasty is equivalent to 400-500 yuan RMB today.
Silver is more active than gold. Although its abundance in the crust is about 15 times that of gold, it rarely exists as a single substance, so it was discovered later than gold.
In ancient times, people already knew how to mine silver ore, because the amount of silver obtained at that time was very small, which made its value more expensive than gold. From BC 1780 to BC 1580, the Egyptian code stipulated that the value of silver was twice that of gold. Even in the17th century, the value of Japanese gold and silver was equal.
Silver was first used as decorations and tableware, and later used as currency.
Silver, namely silver, is called silver because of its white color, as opposed to gold. Think of it as money and decorations. In ancient times, money was called silver. Silver always shines like the moon. The original meaning of silver paper is "bright".
In China, silver characters are also commonly used to describe white and shiny things, such as the Milky Way, Ginkgo biloba, whitebait, tremella, screens and so on.
In ancient China, silver was often juxtaposed with gold and copper, which was called "only gold". Gong Yu records that "gold is the only product", which shows that silver was discovered in China as early as the 23rd century BC, that is, more than 4,000 years ago. In nature, silver often exists in the form of pure silver. People once found a piece of pure silver weighing 13.5 tons!
In addition, it also exists in the form of chloride and sulfide, and often coexists with minerals such as lead, copper, antimony and arsenic.
Industrial application
Electrical products
Electronic appliances are the industry with the largest amount of silver, and their uses are divided into electrical contact materials, composite materials and welding materials. Silver and silver-based electrical contact materials can be divided into pure silver, silver alloy, silver oxide and sintered alloy.
The annual output of silver and silver-based electrical contact materials in the world is about 2900~3000t, and composite materials are prepared by composite technology, which can be divided into silver alloy composite materials and silver-based composite materials.
From the point of view of silver saving technology, silver composite material is a new material with great development prospect. Silver welding materials such as pure silver solder and silver copper solder.
Sensitive materials
Silver halide photosensitive material is one of the fields with the largest amount of silver. At present, several photosensitive materials with the largest production and sales volume are photographic film, photographic paper, X-ray film, fluorescent information recording film, electron microscope photographic film and printing film.
In 1990s, the world photographic industry used about 6000 ~ 6500 tons of silver. Due to the development of electronic imaging and digital imaging technology, the amount of silver halide photosensitive materials has decreased, but the application of silver halide photosensitive materials is still irreplaceable in some aspects, and there is still a great market space.
chemical
Silver has two main uses in this respect. One kind is silver catalyst, which is widely used in redox and polymerization reactions, and is used to treat industrial waste gas containing sulfide. Second, industrial preparations for electronic plating, such as silver paste and silver potassium cyanide.
Craft ornaments
Silver is favored by people (especially women) because of its attractive white luster, high chemical stability and collection and ornamental value. Therefore, it has the reputation of women's metal, and is widely used as jewelry, decorations, silverware, tableware, congratulatory gifts, medals, commemorative coins and so on.
Silver ornaments have a broad market in developing countries, and silver tableware is welcomed by families. Silver commemorative coins are beautifully designed, with small circulation, and have the function of maintaining and increasing value, which is favored by coin collectors and coin investors.
In the 1990s, the amount of silver used for coinage alone remained around 1 1,000 ~11,500t every year, accounting for about 5% of the silver consumption.
References:
Baiyin-Baidu encyclopedia
Platinum-Baidu encyclopedia