The tiny single-celled microorganisms had enough time to develop their own method of breaking down the atoms without the help of an inner cell. These single-celled organisms do their job very slowly compared to the multicellular blobs that bounce around the planet.
These single-celled organisms evolved independently of each other. Some overlapping together, forming domains abundant with those elements. And a rare few dominating areas leading to an overabundance of such elements.
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Another billion years later, the whole planet is now teeming with life. Towering trees dominate the land. Large fish swim through the ocean. The tiny blobs evolved into a bigger version. These blobs developed a core inside their bodies. These cores contain their broken down elements. Such an evolution was beneficial as it helped them store energy for a longer period of time.
