Several centuries ago, a branch of alchemy called chrysopoeia is said to have explored the possibilities of transforming widely available base metals into precious metals. Early practitioners never managed to pull it off, but it appears that in studying the conditions that emerged just after the Big Bang using the Large Hadron Collider (LHC), scientists have turned lead into gold – for just fractions of a second.
Archived version: https://archive.is/newest/https://newatlas.com/physics/lead-gold-lhc-alice-cern/
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If they ever manage to turn lead to gold permanently, then it will put gold mines out of business. Gold prices will go down if they over produce, especially if its cheap to convert lead to gold.