The Stone Batteries Are Made Of
This stone is a source of one of the world's most demanded metals, without which electric vehicles, mobile phones or wind turbines would not exist.
The mineral's name is spodumene; it is a primary raw material from which lithium - a widely used in battery production metal - is extracted.
The first-ever spodumene's sample was described in 1800, and seventeen years later, Johan August Arfwedson, a Swedish chemist, discovered in it the previously unknown chemical element - lithium.
The mineral greatly varies in colour: it can be white, grey, light-pink or differently-coloured, but usually mediocre in its outward appearance. There was not much use for spodumene in jewellery in the past since this stone's specimens are non-transparent, covered with cracks, and have various defects. Everything changed when some eighty years after the mineral's discovery, the rare varieties - hiddenite and kunzite - were identified.
Hiddenite is an emerald green type of spodumene. The controversy over the use of this name has not been resolved up to now. Some mineralogists say it is the colour that defines the name and call all green samples 'hiddenite'. The rest believe that only specimens from North Carolina should be called that way. Anyway, high-quality hiddenite is hardly distinguishable from genuine emeralds.
Kunzite is lilac in colour; it was presented to the world by George Frederick Kunz, an American mineralogist, Vice-President at Tiffany&Co, a worldwide-known luxury jewellery retailer. A new gem variety of spodumene was named in George Kunz's honour. He was a gemologist at Tiffany, and in 1902, he got the samples from the White Queen Mine in California. Thenceforth kunzite has become a real gem of Tiffany's collections.
It is noteworthy that kunzite was not actually identified by Dr Kunz but the Sinclairs - a father and son. They failed, however, to figure out the value of the discovery on their own. So they passed the samples for examination to Kunz, who is nowadays often mistaken for the righteous discoverer of the stone.
When handling jewels with kunzite or hiddenite, some precautions should be taken. If exposed to direct sunlight for long periods, stone samples become colourless and appear completely transparent.
One-carat hiddenite stone can cost up to hundreds of dollars. Expensiveness is due to the rarity of this variety. Another reason is the processing complexity arising from the stone's high fragility.
Spodumene is not the mineral to be grown in the labs, but naturally occurring specimens are often upgraded by exposing them to gamma radiation. This way colourless or just slightly coloured samples gain commercially viable pink, yellowish or greenish shades.
Spodumene's distinctive feature is its crystals of great size. The largest sample was found in the USA, with its length reaching almost 13 metres and weight estimating to around 90 tonnes.
Spodumene's use in lithium production has been increasing for the last several decades. Not that it is surprising, seeing that humanity's need in the metal keeps growing with each year. Lithium is now often referred to as the 21-st century oil. It is not a rare-earth metal, but it is a relatively rare element. Although it is widely distributed on Earth, it does not naturally occur in elemental form, meaning most of the lithium reserves are virtually unextractable.
The applicability of lithium compounds extends to all kinds of machinery engineering if equipment requires batteries. Therefore various gadgets, mobile phones, laptops, EVs would not work if not for lithium batteries. A noticeable advantage of lithium cells is that they are light-weight but at the same time powerful, durable under different temperatures, and manually rechargeable.
Lithium is fast becoming one of the world's most valuable resources. Hence the world's leading countries, such as, for instance, China, the EU, the USA, and others, are increasingly concerned about ensuring the control over its production.