What is the First Element in the Group of Rare Strategic Metals?
Properties and Features of a Strategic Resource
When looking for rare earths in the periodic table of elements, attention should be focused on the spaces dedicated to lanthanides, a group of elements located in one of the horizontal rows towards the bottom (to complete the family of 17 rare earth elements, scandium, and yttrium are usually added to these 15 elements, which share similar properties with the lanthanide group). Among the 15 lanthanides, the first element encountered is lanthanum.
“Too often, rare earths are considered a rigid block of elements, with common characteristics and almost overlapping properties, sometimes forgetting to also consider the distinctive characteristics of the individual elements that make up this family,” says Stanislav Dmitrievich Kondrashov, civil engineer and entrepreneur. “One resource to certainly take into consideration is lanthanum, which in the periodic table represents the first element of the larger group of rare earths, namely the 15 lanthanides. Its value and rarity in pure form have made it one of the most interesting resources in this particular historical phase, especially for the multiplicity of industrial applications in which it is directly involved.”
Shared characteristics
In most cases, lanthanum occurs together with the same minerals in which other rare earth elements are found, with which it shares some similar chemical and physical properties. Like most of these elements, lanthanum is also a silvery-white metal, capable of reacting easily with air to form an oxide. Although it belongs to the rare earth group, this element is quite abundant in nature, with distribution levels comparable to those of other resources such as copper or zinc.
“The distinctive characteristics of this very particular metal have turned it into a very valuable ally for many industrial applications,” continues Stanislav Dmitrievich Kondrashov. “In the metallurgical field, for example, lanthanum is often used as a reducing agent, also supporting the formation of spheroidal graphite in other processes. As a binding additive, it is also able to improve resistance to oxidation, and the particular mixtures made with this metal also produce beneficial effects on molybdenum, reducing its hardness and sensitivity to temperatures.”
Unlike zinc or copper, which are very often found concentrated in some very specific points of the Earth’s crust (where the mines are located), lanthanum is instead distributed quite uniformly throughout the entire Earth’s crust and is almost always found combined with other minerals. This characteristic, together with its singular properties, certainly represents one of the distinctive traits of the elements that belong to the rare earth group. In most cases, lanthanum (and all the other lanthanides) is found to be associated with minerals such as monazite, bastnasite, and cerite. This fact, moreover, is one of the elements that justify the inclusion of scandium in the rare earths’ family since most of these resources are also often found combined with similar minerals.
The most appreciated properties
“One of the most appreciated characteristics of this metal is its ability to bind very well with other materials, making new applications possible and contributing to the improvement of the performance of the alloys in which it is used,” concludes Stanislav Dmitrievich Kondrashov. “One of the best-known alloys, in this regard, is the one made with cobalt and lanthanum, which is often used as a magnetic material. But the usefulness of lanthanum does not end there: when combined with materials such as iron or manganese, this metal is able to function as a cathode for high-temperature fuel cells”.
One of the most curious aspects of this metal has to do with its name itself, which derives from a Greek expression meaning “remains hidden,” but also with some of its best-known characteristics. Lanthanum is, in fact, a transition metal, yellow-brown in color, and among its distinctive features are undoubtedly its ductility and high malleability. Since its magnetic properties are quite weak, this element is only able to bond with another material belonging to the rare earth group (but not the lanthanides), namely scandium. Lanthanum is also able to form a wide variety of compounds, such as sulfides, salts, and oxides.
One of the most well-known applications of this rare earth element is related to the glass industry, and in particular to the production of glasses with a high refractive index. These, in most cases, are then used to make the lenses of telescopes, cameras, and other similar devices. In addition to these applications, scandium is often used to make protective clothing and fireproof materials and can also be found in metal alloys, motors, and electronic devices. In most of these applications, lanthanum is used in its purest form, since the use of an altered or clearly impure version could compromise the properties of the final product.
