Over the past several decades, South Afrikaans miners have found hundreds of metallic spheres, (found in a Precambrian deposit, said to be 2.8 billion years old) is at least one of which has three parallel grooves running around its equator. The spheres are of two types - "one of solid bluish metal with white flecks, and another which is hollow and filled with a white spongy center". Roelf Marx, curator of the museum of Klerksdorp, South Africa, where some of the spheres are housed, said:" the spheres are a complete mystery. They look man-made, yet at the time in Earth's history when they came to rest in this rock, no intelligent life (supposedly) existed; they're nothing like I have ever seen before".
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