Aluminium is literally one of the most common elements on Earth. So how did it come to be that aluminium cost more than gold? Was it similar to how the relatively common and easily acquired mined diamond came to be seen as valuable in the last century due to strict control of supply to consumers and some of the best marketing the world has ever seen? (For reference, the cost of mining a 1 carat diamond is about $50, though it sells for drastically more than that, even low quality ones for industrial use. On the high end, suitably high quality ones will sell for, on average around $25,000 once cut and polished, generally by cheap labor in places like China.)
The simple answer is that although aluminium makes up about 8% of the Earth’s crust, it has never been known to occur in its metallic form anywhere on Earth. Instead, aluminium appears mainly as a chemical compound across the globe, for example inside potassium aluminium sulfate.
Before aluminium was discovered, or even theorised, so called “alum compounds”, like potassium aluminium sulfate, have been used extensively since antiquity for everything from leather tanning to fire-proofing. In fact, potassium aluminium sulfate (colloquially known as potassium alum) is still used today in things like aftershave and baking powder and most awesomely of all, in its crystal state it can be used as a “deodorant rock” that you rub on yourself to eliminate body odour.
Now, at first glance it would seem like these chemical compounds are referred to as “alum” because they contain aluminium, but this isn’t the case. The word “Alum” is the colloquial name given to a wide range of compounds that don’t necessarily include aluminum, for example chromium potassium sulfate which is commonly shortened to chrome alum. The word aluminum itself is a derivative of the the word “alum”, not the other way around.
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