One level back to [Semi-metal oxides]. 2.2.3.3.3.2.1.2.1. [Quartz] (silica, silicon dioxide SiO2) [Rock crystal, opal, amethyst] 223332122
One level back to [Semi-metal oxides]. 2.2.3.3.3.2.1.2.1. [Quartz] (silica, silicon dioxide SiO2)

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[Quartz] (silica, silicon dioxide SiO2)