The microscopic particles of gold can be found in plants like eucalyptus and Norway spruce, which absorb it from the soil through their roots. This process, which is not economically significant for large-scale mining, occurs when roots encounter gold-bearing rock and the plant transports tiny gold particles through its vascular system, storing them in the leaves. Recent research even suggests microbes may help transform and lock the gold into nanoparticles within the plant tissue.
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