The last mineral family before the branch fork in Bowen's reaction series, they have orthoclase and plagioclase forms.
The composition of this group can generally be expressed in terms percentage albite, anorthite, and K- endmembers. Molecules of all members of this family contain eight oxygens and are aluminosillicates with traces of potassium, calcium, or sodium. Members of this mineral family include labradorite, perthite, sanidine, and microcline. The last mineral family before the branch fork in Bowen's reaction series, they have orthoclase and plagioclase forms. FTP, name these minerals that make up the majority of the Earth's crust.
The composition of this group can generally be expressed in terms percentage albite, anorthite, and K- endmembers.
feldspars