Aluminum used to be more valuable than gold!

I DONT KNOW HOW THATS POSSIBLE

what is the actual reason and consequences behind this fact?

maby beacuse it is a very light metal, so in medieval times weapons made out of alumunim were the easiest to handle making aluminium valuable

Correct.... Before 1884, the value of aluminium was priced at 200,000$ per kg... This was due to the fact that it was very difficult to extract the pure aliminium metal. Napoleon III even gave his silver silverwear to his servants and got himself some aluminium silverwear instead in 1854. It was until 1884 that Charles Martin Hall (American) and Paul Héroult (Frenchman) discovered a way to obtain aluminium very cheaply. The process consisted in mixing the alumiumoxide with kryolite, making the melting point to drop to ~1000°C instead of the usual 2250°C!