each 2 1/4 inch diameter. Moqui Stones (or Balls or Marbles) or Kansas Pop Rocks. These stones are said to come in two genders, the smooth version being ââ¬Åfemaleââ¬Â and the jagged version being ââ¬Åmaleââ¬Â. Found in only a few places in the world, these ovoid iron-pyrite formations have been the talk of spiritual circles for years.