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Classification of rare metals
Source: Network
Release time：2023-10-12 14:24
According to the physical and chemical properties of various elements, occurrence state, production process and other characteristics, rare metals are generally technically divided into the following five categories:
Rare light metals include lithium, rubidium, cesium, beryllium. Small proportion, strong chemical activity.
Rare refractory metals include titanium, zirconium, hafnium, vanadium, niobium, tantalum, molybdenum, tungsten. The melting point is high, and the melting point of compounds formed with carbon, nitrogen, silicon, boron, and the like is also high.
Rare dispersed metals are referred to as rare metals, including gallium, indium, thallium, germanium, rhenium, selenium and tellurium. Most of them occur in minerals of other elements.
Rare rare earth metals are referred to as rare earth metals, including scandium, yttrium and lanthanides. Their chemical properties are very similar and they are associated with each other in minerals.
Rare radioactive metals include naturally occurring francium, radium, radon, thorium, and uranium in the polonium and actinides, as well as artificially produced technetium, promethium, other actinides and elements 104 to 107.
The above classification is not very strict. Some rare metals can be included in one category or another. For example, rhenium can be included in the scattered metals, but also can be included in the rare refractory metals.
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