Over the past few decades, miners in South Africa have been digging balls mysterious metal.
Its origin is unknown, these balls about an inch in diameter or more, and some are etched with three parallel grooves along the diameter of the sphere.
Two types of balls have been found: one is composed of a solid bluish metal with white spots, others are hollow and contain spongy white substance.
The great thing is that the rock on which balls were found came from the Precambrian era - and old 3.8 billion years! Who made these spheres and for what purpose, was not known until now. VIDEO
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