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Facts About Scandium

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سُئل يناير 20، 2022 في تصنيف ريكي بواسطة heatedeg

 

Scandium is a silvery metal that is soft and has a density of about three times that of water. Scandium is a transition metal and is also considered a rare earth element due to similar chemical properties (such as difficulty in extracting and in separating from other elements) and existence in the same ores, according to Chemicool.

Scandium is the 31st most abundant element on Earth, according to Periodic Table, with about 22 parts per million abundance by weight in Earth's crust, according to Chemicool.

 

Scandium is scattered thinly and has been found in over 800 minerals. Within these minerals, scandium is found in its oxide form (Sc2O3, also known as scandia or scandium oxide), according to Scandium Mining. There are many commercial uses for scandium even though the cost of scandium is typically high – several thousand dollars per kilogram for scandium oxide and up to a few hundred thousand dollars per kilogram for pure Scandium Metal, according to Chemistry Explained.

 

History

Russian chemist Dmitri Mendeleev, inventor of the periodic table, predicted the existence and properties of scandium (which he called "ekaboron" — similar to boron) in 1869, according to the New World Encyclopedia. Lars Fredrick Nilson, a Swedish chemist, when examining the spectra of the minerals euxenite and gadolinite, discovered the element in 1879. The element was named for the Latin word for Scandinavia, "Scandia," due to the minerals in which Scandium Oxide was at that time found to exist only in the Scandinavian Peninsula, according to Peter van der Krogt, a Dutch historian. Per Teodor Cleve, a Swedish chemist, made the link that the new element discovered by Nilson was the same as the proposed element described by Mendeleev.

In the first attempt to isolate scandium, Nilson and his team processed 10 kilograms of euxenite and were able to produce about two grams of scandium oxide. According to the New World Encyclopedia, metallic scandium wasn't produced for the first time until 1937 by Werner Fischer, Karl Brünger, and Hans Grienseisen, German chemists. In 1960, 99 percent pure scandium was produced.

 

What is a master alloy and how is it different from a traditional alloy? And why is the use of Master Alloys so important in the field of jewelry? We find out in this article.

 

Most of the alloys in our catalog fall under the definition of master alloy and the question of what exactly is meant by this definition may arise.

An alloy is a compound made up of two or more elements, of which at least one is a metal. The characteristics of an alloy such as hardness, strength and even color are generally different from those of the elements that constitute it, for example copper and tin, both relatively soft, form the more resistant bronze.

An Aluminium Based Master Alloy is a particular type of alloy designed to be added to a pure metal, in our case gold or silver, in order to modify its characteristics. A pre-master alloy is a master alloy from which a fundamental element has been subtracted. In our field, it is generally a master alloy from which silver was stolen for logistical reasons.

 

Why it is necessary to use a master alloy?
Most Pure Metals are not suitable for technical applications. Pure gold, for example, is extremely soft; this feature makes it easily workable and is one of the reasons for its success in jewelry, but a jewel made of pure gold would easily bend if treated without too much care and would not have sufficient wear resistance. The same considerations apply to silver. For this reason, pure gold is generally transformed into a gold alloy, according to the standard proportions indicated in twenty-fourths, or carats (K).

 

Until the Second World War, the most popular alloys were mainly formed by three elements: Gold, Silver and Copper.

 

With the evolution of technique, jewelry has required increasingly specialized performance from alloys, this has led to the need to study the use of new elements to be added to precious metals, which are able to drastically change their characteristics. So we went from having alloys composed of two or three elements, to new formulations that come to contain even 10, effectively increasing the complexity of the product.

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