1) Phosphate mineral 
Berlinite (aluminium phosphate, chemical fomula AlPO4) is a rare phosphate mineral. It has the same crystal structure as quartz with a low temperature polytype isostructural with α–quartz and a high temperature polytype isostructural with β–quartz. Berlinite can vary from colourless to greyish or pale pink and has translucent crystals. It wa...