One level back to [Oxide salts]. 2.2.3.3.3.3.2.1. [Non-metal oxide metal]. 2.2.3.3.3.3.2.1.1. [Phosphates] (turquoise, purple, etc.) 2.2.3.3.3.3.2.1.2. [Sulphates and sulphites] (gypsum, alabaster, baryte, etc.) 2.2.3.3.3.3.2.1.3. [C-N-oxide metal] One level further to [Phosphates] (turquoise, purple, etc.) One level further to [Sulphates and sulphites] (gypsum, alabaster, baryte, etc.) One level further to [C-N-oxide metal]

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[Non-metal oxide metal].