Incredible world with unsolved mysteries

Our world is full of strange and mysterious things that we humans can’t understand and explain yet. These are 10 unsolved mysteries of our world that will remain us shocked.   Grooved Spheres   Precambrian, a rock found in South Africa was considered to be mysterious when some metal spheres were found in them. The rock being 2.8 billion years old had these 1 inch diameter metal spheres and three parallel grooves etched around the eq...