New answers tagged


Olivine is a solid solution between forsterite and fayalite, so it is generally expressed as molar percentages of these end-members, for instance Fo80Fa20. Often only one end-member is mentioned, as it is sufficient to infer the other (their sum is always 100 %). It is the same with plagioclase, which is a solid solution between albite and anorthite and is ...

Top 50 recent answers are included