Primary/secondary minerals

Some secondary mineral are created as a result of partial change of crystalline structure of some other mineral (either primary or secondary). Example of that is weathering through hydration of hematite to limonite (see lecture notes from Jan 9). In addition, some other secondary mineral are created as a result of complete destruction of crystalline structure of another mineral that releases various ions into soil solution. New (secondary) minerals could be created in soil from those ions