Geode conforming to Wikipedia. Result of the formation of bands in the variable geode iron oxides transmit siliceous solutions to rust, generally observed with quartz.
Quartz in keeping with Wikipedia. Quartz, silicon and oxygen continuous structure tetrahedra containing oxygen between tetrahedra, global chemical formula.
Quartz the quartz information images as reported by Minerals. Quartz most minerals of the earth. Essentially important constituent rocks. The most varied quartz occurring different habits, colors.