-on-column color doubleside ring spin" animation__spin="dur: 6000"></a-entity>
          <a-entity mixin="object-on-column color doubleside ring spinX"></a-entity>
        </a-entity>
        <a-entity mixin="column-bottom"></a-entity>
      </a-entity>

      <!-- Spheres. -->
      <a-entity position="2.5 0 -2">
        <a-entity mixin="column">
          <a-entity mixin="column-light"></a-entity>
          <a-entity mixin="object-on-column color sphere yoyo"
                    animation__yoyo="property: