NASA’s Mars Rover Curiosity discovered plentiful indigenous spherical ooids at High Dune and Namib Dune in Bagnold dune field, Gale Crater, Mars. The spherical Martian ooids contain nuclei and range from around 0.15 mm to 0.5 mm in diameter. Colors of the spherical Martian ooids are various, including white, yellow translucent, green, gray, and yellow. The spherical Martian ooids should have been ... [Show full abstract] formed by microbes, because ooids of Earth have recently been found to be formed by microbes and microbial borings are found in ooids of Earth and of Mars. There is no evidence that proves ooids are formed by agitated water.