What is the ratio of potassium to aluminum to oxygen in feldspar?

Feldspar is a group of minerals that typically includes potassium feldspar (orthoclase), which has the chemical formula KAlSi3O8. In this formula, the ratio of potassium (K) to aluminum (Al) to oxygen (O) is 1:1:8 when considering the composition in terms of K, Al, and O. This means for every one potassium atom, there is one aluminum atom and eight oxygen atoms in the structure of potassium feldspar. Other feldspar varieties, such as plagioclase, have different ratiOS.