The formation of Mercury remains an unsolved mystery. The planet closest to the sun has a disproportionately large metallic core—accounting for about 70% of its mass—and a relatively small rocky ...

Amethyst is a violet variety of quartz which has been used as a gemstone for many centuries and is a key economic resource in northern Uruguay. Geodes are hollow rock formations often with quartz ...

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Scientists have figured out how proteins may have been created on early Earth. When a bone grows, our bodies’ proteins help provide the structure. When a muscle tears, proteins help rebuild it. When ...