Question: what is the empirical formula of the mineral having?
Answer: The chemical formula means that in quartz, the ratio O:Si is always 2:1. OLIVINE, on the other hand, is a good example of a mineral with a restricted range of composition. It's chemical formula can be written (Mg,Fe)2SiO4. The chemical formula means that the ratio O:Si:(Mg+Fe) is always 4:1:2.