Glossary of Terms

Feldspathoid group

Group of minerals that are similar to those of the feldspar group. The difference is that the feldspathoids lack the amount of silica to fully make them into feldspars during the formation process. They, as feldspars, are aluminum silicates of potassium, sodium, and/or calcium. The feldspathoid group is in the tectosilicates subdivision of the silicates group.